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£ « c e b 0 g<br />

ixn ttnt !8?(it^ematif<br />

bit)<br />

Dr. (3 eox Q g r. U r f i n.<br />

fV\at\'WVWM/VW\\IV\'WVVVUi«<br />

2( n b c n 2> e c I ,<br />

inbe^olbenbe<br />

©fercomefrien/ Sngonometnen/ HtQihta 09 bet<br />

^ j 0 b e n 1) a » n.<br />

Slrijft i £l;iele« SBogtryftetie.<br />

18 2 4.


^'laroarenbe anben ®eel af ben af mig i Sldvet 1822 ub:<br />

flione Sarebog i ben rene SRat^ematif fremfommer ifar oeb<br />

ct


YI<br />

^ilberne ifte ere anferte, ter jeg bog iffe Ealbc nogenfomI;el|t<br />

^er frcmfat 2l;eorie min egen, ©om Jorfatter af et Siemens<br />

tars93arE Ijaobe jeg oel be^nben 3iitet at gjere, nbcn at oalge<br />

gjjaterialier og famie biffe til et ^eelt; og, ^ar nu felo bette<br />

asalg ilunbom Eunnet ubftraEEe fig til Mffnit, fom ei tilforn,<br />

i bet JKinbfte iEfe paa benne 2Raabe, ere fremfatte i Sare:<br />

begerne, ia oil man natnrligft fege ©runben I;ertil i ben<br />

2Kaabe, I)Oorpaa mit ^ele ©tubinm er lebet, ligefom cgfaa,<br />

cm man paa flere ©teber (!ulbe fpore en x>ii ^jarlig^eb for<br />

ben matOematiffe Salcul, I;«iIEen jeg l)aaiit £aferen oil belc<br />

meb mig, ia oil benne albeleg labe fig forElare af min ©til:<br />

ling og ®annelfe unber oor beremte 3I|lronom sprofeffor 03<br />

9iibber @c^umac()er.<br />

5(nmartningen til §, 4 ©ibe 38 ter jeg nu foranbre ber:<br />

^en, at, oeb ben Sntereffe, ber nbenlanbg er oaft for Soga:<br />

ritl)mcr meb 6 ®ecimaler, og oeb .fijalp af ben ©ubfcription,<br />

?)oormeb man l^ar bearet mig, feer jeg mig iflanb til at reali:<br />

fere bet ber pttrebe ^aab. ©amtibigen meb bette ©Eriot<br />

forelagger jeg faalebeS mine fianbe^manb qjlanen til Sogaritft:<br />

merne og be ©ubfcription^ :2>iIEaar, jeg fortringoiig tan til:<br />

6i)be im, Snljoer ^eroarenbe ©ubfcribent oil, foruben ben<br />

asiftanb, ber ^iei mig fom ene gorlagger af et faa bctpbeligt<br />

goretagcnbe fom ooennaonte gogaritljmer, og I}oilEen jeg (Icbfe<br />

taEnemmeligen oil erEjenbe, tiHige i gorbinbelfe meb be ©itb:<br />

fcribenter, jeg iibenlanbg ^ar, bibrage ©it til at fremme et<br />

2Sarf, t)oie ©aon lange felteg, og i)vii asrugbar^eb neppe<br />

oil bctoioleg, naar mine drafter ellerg formaae at ubfere bet<br />

faalebeg, fom bet af mig, fom Sorrecteur 03 Ubgioer, meb<br />

a3illigf)eb fan traoe^.


© c 0 m c 11 i c.<br />

"iiniin 7tfbcling. ©tcreometrie.<br />

§. I. © r u n t) f. (It spiang SSeltggen^cb er 6c(!cmt<br />

ucb tre QJunctcr, fom iffe ligge i en ret Sinie.<br />

Sill. I. ?o rette 2inicr, ber ft0be fammen i ct<br />

^unct, ubcn enten albclcg at falbe fnmmen cller »ffre ^in;<br />

nnben lige mobfatte, bcftcmme ogfaa et


en^«cr Sinie, ber brage^ igjennem fatnme ^unct t bit


$. 6. Sa'ref. Srcier en ret SDinfcl fig om fit cue<br />

S:ccn, fna bcfTiiocv tct nnbct vcb |ui Ombrctning ct 'plan.<br />

25 c i\ 5lntag at ben rette a3infel »cb fin Ombrcining<br />

iffe fiar biinnct et 'Plan, fan conflvuecr et Q)lan MJVJ_AC<br />

i'Monncm C (§. 4 5itl. 2). 3l'ntng nu gjcnnem AC et 'Plan<br />

Ingt pan ct vilfnnrligt 2tcb, fan vil bet tTjffre MN t en ret<br />

Sinie, f. Sr. CD og ben frembragtc Jlnbe t en anben ret Sinie<br />

CB, men beggc biffe ere "Perpcnbicuterer t fammc ^lan til<br />

AC, ^vilfct er umuligt. ©aolebc^ fan beoifeg, at MN (U<br />

^»crt 2tcb fnlbcr fammen meb ben frembragtc globe, eller<br />

at benne cr et QMon.<br />

§.7. £(sref. ©tooe to Sinier lobrette poo fomme<br />

Q3lan, bo ere biffe paroUcLfc.<br />

95 eo. Soreen B og D meb en ret Sinie, oprci^ t ^(.<br />

MN Sinien DE J_ BD, gj0r AB = DE, brogeg nu BE 03<br />

AD, fan cr AABD S BDE; oltfna AD = BE; brogeS<br />

AE, fofl cr A ABE S AED, altfnn Z_ABE = ADE, men<br />

ABE z= R, oltfnn DE J_ AD, og tiUigc er DE _L BD 03<br />

DE _L DC; nitfno AD, BD og CD i eet ^Mon, t ^oilfet<br />

cgfoo AB liggcr. 3 bette Q31an over|Tj«reg AB og DC of<br />

BD, bo nu /_ABTi -f- BDC = 2R, foo er AB =^ CD,<br />

§.8. £ « r e f. Sr een of to 'PoroUeller lobret poo<br />

et ^Inn, faa er ben onben bet ogfaa,<br />

95 eo. 2l'ntag AB ± spi. MN, Qjev fomme €onftruc;<br />

tton fom §. 7. 9)u 6e»iftcg let of 'Jrinnglernc^ Congruent^<br />

nt DE J_AD, falgcligen poo $ilonet ABD, ^»ori ogfaa bm<br />

nnben 'Parallel CD finbc^; oltfoa CD j _ DE og tilltge bo<br />

AB =^ CD og /_AED = R, er iL.CDB == R, oltfoo<br />

CD J_ BD, f?lgcltgen CD ± ^l, MN (§. 4).<br />

I*


4<br />

§. 9« £n;r«f- ^^^ f" ^'"'^'^ pornUcUe meb een og<br />

fomme treble, bo ere be inb6i)rbeS poroUelle.<br />

93 6 6. OpreiS fro ct vilfoorligt 'Punct i ben fffllebiS<br />

^oroUcl en 'perpenbicuter i ^»crt of be pornacUe Stnier«<br />

^loner; teg gjcnnem biffe 'Pcrpenbicuterer et 'Plnn. ffla ec<br />

ben fffllcbg 'PoroUel lobret pon bette ^Mon, oltfoo og be to<br />

onbre Sinier berpnn lobrette (§. 8) og f^lgeligcn poroUcHe<br />

(§. 7)*<br />

§.10. ^pg. Sro et spunct ubenfor et 'Plnn at<br />

falbe cu 'Perpenbicuter poo 'Plnnet.<br />

Op[. ®'^"9 ' 'pinnet en vilfonrlig ret Sinie BC; teg<br />

et 'Plon igjennem A, B, C og i bette f«lo AD _L BC. etnaer<br />

AD uu lobret pno MN, fnn er Oplasningcn f«rbig, i)vii iffe<br />

brng DE _L BC t, 'Pl. MN, og fco A ffflb t et 'Plnn logt<br />

igjennem A og DE Sinien AE j _ DE, fan cr AE _L 'Pl. MN.<br />

95ct). 3 'Plnnet MN brag GH z^ BC; nu er BC<br />

J.


i ^vert *pian fra ct vilfoorligt "Punct i 'pionerneg OvcrjTjff;<br />

ringgj Sinie.<br />

§.13. £«rcf. Sro et "Punct i et 'Plon funne iffe<br />

flere enb een Sinie oare oprcifle pcrpcnbicute'rt.<br />

95 e t). 3lntog ot ber vare to 'Pcrpenbicuterer, fan teg<br />

tgjennem bcm et 'Plon, fom vil ovcrfFjere bet gi»ne t en ret<br />

Sinie; pao benne vilbc oltfoa i eet "pion beggc 'Perpenbicu;<br />

tercr flnne lobrette.<br />

§. 14. ixvef. Srn et Q)unct ubenfor ct 'Plon fan<br />

tffun ffflbeg en 'Perpenbicuter neb pno 'Plnnct.<br />

95CD. Ser ^oor be to 'Pcrpenbicuterer, om biffe gn;<br />

vti, ftabte pan 'Plnnet, brng en ret Sinie i 'pinnct; ^erveb<br />

vilbe opflnne et 'Srinngel, fom ^ovbe to rette SSinflcr.<br />

§.15. S«ref. ©tnncr en Sinie perpenbicuter pno<br />

et 'Plan, bo fraacr et^scrt "Plon, logt gjcnnem ben, lobret<br />

pao bette Q3lan.<br />

95CO. ©tflocr AB X ^1. MN, faa noar berigjennem<br />

teggc^ ^1. CE, l)»ig 0»erfTj«ringg-• Sinie meb MN cr CD,<br />

fan er AB J_ CD; brngeg nu BF JL CD, fnn er ^ABF<br />

Snclinntiong,-Sinflen for ^Innerne; men benne «• R, bo<br />

AB ± "Pl. MN.<br />

Sill. ^00 @runb ficrnf fnn et 'Plnn igjennem en<br />

ret Sinie i et onbet 'plan fcette^ perpenbicutert poo bette.<br />

§. 16. £(Ercf. ©tooer et 'Plan lobret pan ct onbet,<br />

bo cr ben Sinie, ber i bet cue Q3lan er brogcn lobret poo<br />

C»crfFj


£ t f f. ©tfloe to planer lobrette poo et trebie, bo fnn<br />

biffe iffe ^ave fnmme 0«evfFjunct.<br />

§.17. icei'tf. ©tone to pinner lobrette poo ct tre;<br />

bie, ba er berc6 OoerfTjffringg--Sinie lobret pan bette.<br />

S5 c t). @tob AB iffe lobret pon ^1. MN og f^Igcligen<br />

ci feller paa CD og EF, foo lob poo CD t ^l. CK en on;<br />

ben perpenbicuter, GB, jtg opreife, ligelebel i ^lonet EL<br />

^erpenbicuteren AB; beggc biffe Sinier vilbe jlooe lobrette<br />

paa MN (§. 16), ^vil^et ftriber mob §. 13.<br />

§. 18. Sf f. '^0 planer ere pnrollclle, noor be, t^vot<br />

Jnngt be enb fortenge^, olbrig labe fommen.<br />

§.19. £«rcf. ©tfloer en ret Stnte lobret p^o to<br />

^loncr, bo ere biffe poroUelle.<br />

95et). OverfTjore be ^inonben etftebg, bo lob ber ft3<br />

fro et ^unct i OBerffjacinge; Sinien til ber, ^vor Q3erpenbi;<br />

cuteren trof ^Innerne, c begge ^lonerne broge rette Sinier;<br />

foolebeg vtlbe opftooe et 5riongel meb to rette SSinfler.<br />

§. 20. S«rcf. OtJcrfFjffreg to poroaellc QJloner of<br />

et ^lon, bo ere OvcrjTjffringg 5 Sinierne pnroUelle.<br />

95et). 5rof be fommen, foo mootte ogfoo 9>Ianerne,<br />

tilftrffffeligen fortengebe, trcpffe fommen.<br />

§.21. £a;ref. ere fro et ^lon til et onbet, fro tre<br />

^uncter, tre 'Pcrpenbicuterer falbebe, 03 bijTe ere ligeftore,<br />

fco ere 'Ploncrne poroUelle.<br />

35et). Sre AB 03 DC perpenbicutere poo MN, fao<br />

er AB rjt DG (§. 7) 03 tillise efter 3fntogclfcn ligeftore; bro;<br />

Seg nu AD 03 BC, foo er AD =^ BC (i. §. 65), ligeiebeS


DE rfz CF; bfl nu ^DCB = R 03 DCF = R, faa<br />

er ^CDA = R 03 /_CDE = R, nltfao DC J_ "PI.<br />

PQ (§. 4); bo tiflige DC _L ^1. MN, foo er PQ qfc MN<br />

(§. 20).<br />

§.22. £ffrcf. SBIive to rette Sinier oBcrfFoorne of<br />

Ijarallelle "pioner, bo ere Selene of bcm proportionole.<br />

Set). 3l'nta3 MN, PQ 03 RS povoUelle, foo er AE: EB<br />

= CG:GD; t^t bro3eS en Sinie fro A til D 03 et 'Plott<br />

teggeg gjcnnem A, B og D, foo opflaaer AABD; ^vori EF<br />

r^ BD (§. 20), nltfao AE:EB = AF:FD; men lige;<br />

Icbcg AF : FD = CG : GD, oltfoo AE : EB = CG: GD.<br />

§.23. £


8<br />

jiem ^uert 'Por ^oSliggenbe tegge^ pinner; ben jjuul^eb, ber<br />

bo cr mcttem be i eet Q3unct fammcnflfibenbe Q:)loner, er bett<br />

legcmlige SSinfcI.<br />

©e plane SSinfler, fom inbcflutte ben legcmlige SSinfcl,<br />

falbeg bcn^ ©iber, eg 3nclinationg;a3iuflcrne racltem to<br />

^oSIiggenbe 'pinncr J?j0rnet^ SSinfler.<br />

§. 26. £ a; r e f. 3 et^vcrt trefibet S^jmxt er Sum?<br />

men of be to Siber flebfc ftwre enb bm trebie.<br />

95et). (£re olle tre Siber ligcftore, foo inbfcc6 let,<br />

nt be to (Eiberg ®um er ftarrc enb ben trebie, ^vi^ iffe,<br />

fan ontng z_BAC < CAD eg gj0r ^CAE = BAG, tib<br />

lige AE = AB; tng AC of vilfoorlig Sffngbe og bro3 CD<br />

03 BD; nu er A ABC S! CAE, oltfoo CE = BC, men<br />

CB -f. BD > CD, oltfoa BD > ED. 3 be to 'Srinngler<br />

ABD eg DAE ere to ©iber ligcftore, men BD > DE, olt;<br />

foo /_BAD > DAE, og z_BAD -f BAC > CAD.<br />

§.27. £(Bref. 3 ct^Bcrt jjjwne er Summen of<br />

olle ©iberne tilfommen minbre enb 4R.<br />

Set). Ot)er)Tj«r otic X?j«rnetg ^onter veb et 'pinn<br />

BCDE. SHu er i bet trefibebe J?j0rne, veb B, Siben EEC<br />

< ABE + ABC; ligelebe^ BCD < BCA -f- ACD jc; men<br />

bn BCDE er en giirfont, ere z_ EBG -f- BCD -f- CDE +<br />

DEB = 4R, oltfoa ABE + ABC + BCA -j- ACD -f- ...<br />

> 4R; men biffe 8 Siber ubgjarc tilligcmcb Jpjernct A'g<br />

eibcr tilfommen sR, oltfoa er Jjjernetg ©iber minbre enb<br />

4 R. Set ©nmme bcvifteg om etf)Bect jpjsrne of et vilfnor*<br />

ligt 2lntnl ©iber.<br />

§. 28. gn. et «PriSmc er et Scgeme, ber 6e«<br />

gi-ffnbfcg of to pnroaelle globcr, ber ere congrucnte retlinebe<br />

^lon.-Sigurcr og forveften of 'Poroaelogrommer, ber forene


MiTc 'Jignrcr^ ccnilioin-nbe ©iter, dfterfom be to pnrnllclle<br />

glrtbcr, ber tol^c-o Oirun bf Inbcr, cie ^rinnglcr, giir<<br />

fiintcr, Scmfanrcc jc, ben 'Pri^mct trefibet, fiir»<br />

fibet, fenifibet ;r.<br />

9<br />

(En 'PI; rami be cr ct Scgeme, bcgvo-nbfct nf 'Plancr,<br />

fom (tflbc fnmmen i cct 'PMmct, eg ere oprciflc fra ct 'Plon,<br />

fom fiiL\v Ci) V u 11 b f I c, b 0 n. 'Pi;rnmibcu» C:H-mibfIabe bli?<br />

«cr fa,ilc?'Cf en rctlinct 'pimuSigur, og cfter bcnS ©iberS<br />

2tntnl [I'Uitvr.ci 'PiUMiiiibcn, ncmlig trefibet, fiirfibct, fenv<br />

ftbct :c.<br />

§. 29. £a;ref. (Sr et Scgeme 6egrfl?nbfct nf 'Plnncr,<br />

f)vornf be mobftnnenbe ere pnroUctle, bo ere biffe 'ParoUclo;<br />

grniiimcr, og be mobftanenbe congrucnte.<br />

Set). 3l't be bcgvanbfcbc 'pinner ere 'Pnrnllelogrammer,^<br />

tnbfeeS let ifolge §. 20. Sc mob|tnaenbe 'ParoUelogrommcr ere<br />

ligcjlove, t^i brngcS Singonnlcrne CB og EG, foo ligge biffe<br />

t eet 'pinn; tl)t EC z:^ AH, GB =^ AH, oltfnn GB =^ EG<br />

(§. 9). 'Jiaigc er CE =z BG, altfno er og CB = EG,<br />

felgcligcn A ABC ^ HEG. Stgelcbeg CBD ^ EGF, alt;<br />

fnn Qinrollclogrommet AD ^ HF. ©oolcbcg fore^ 5Bcv>ifet<br />

for be evrige 'pnrnllclogrnmmer.<br />

pebon.<br />

Sill. (St fnnbnnt Scgeme folbeS et Q30ro 11eIept;<br />

§. 30. £a:ref. 'porallclcpipebcr, ber f!aoe mellem<br />

fnmme pnrollclle "pioner pno fomme ©runbflabe, ere lige;<br />

|!ore.<br />

«8ct). 95ctragtcS (Sig. a) be to trefibebe "Primmer<br />

BLEI og DFMK, fnn ere ©runbflabcrne congrucnte, og til;<br />

lige fan bet let inbfcc^, at 'PriSmccne ville bffffe ^inonben.


10<br />

(Eubtro^ereS nu DPLI 03 obbere^ EPFN, foo er^clber 'Pa><br />

rollelepipebcrne EC eg FI.<br />

Stgge berimob 'PoroUelepipeberne AF 03 EK iffe foo;<br />

lebcg, ot ©ibcflabcrnc ere t eet 'plan, foo, nonr (Jig. b)<br />

BF eg AH fortengcg eg ligclcbc^ FK og EI foitenge^, op;<br />

ftnoer et nt)t ^ornllelepipebon FN, fom er ligeflort foovel<br />

meb AF fom EK, oltfoa biffe inbbprbc^ lige(!ore.<br />

ZiH. SSeb i?j«lp ^crof fon mon tffnfe jTs et ^nrol;<br />

lelepipebon forvnnblet til et onbet pnn fnmme ©runbjTobe;<br />

men ^viS ©ibelinier (looc lobrette pno ©runbfloben.<br />

Gt fnobont 'Porotlelcpipebon folbe^ et ret, t SJiobffft;<br />

ning til be, ^vis ©ibelinier iffe ere perpenbicutere, og fom<br />

fnlbcS jTjffoe.<br />

§. 31. £a:rcf. J;nvc§ et QJnrnllclcpipebon (AF), 03<br />

i en ©ibeflnbe (HF) to ^cSli3genbe ©iber (HG 03 GF) f)aU<br />

vereg, og igjennem Selinggpunctcrne brageg Sinier (LM og IK)<br />

jjnrollelle meb be mobf!nnenbe ©iber, 03 t3jcnnem biffe ottec<br />

te3geg 'Ploncr porollelle meb be mobftnoenbe ©tbcflnber i<br />

^ornllelepipebet, fon ere be pre becveb epfemne ^orotlelepi;<br />

peber congrucnte.<br />

95ct). HT, TG, TF eg EF ere congrucnte ^nrolle;<br />

losrommer, tiUise ere 'Porollelcpipcberneg 3nclinntion6;aSiii;<br />

flcr ll3eftere (§. 23), foolebcg ot biffe funne Bruges til<br />

Safning.<br />

Sill. SrngeS cnbnu fro D til B eg fi-o E og G<br />

vettc Sinier, fon ere biffe porollelle, bo DE er porollel og<br />

ligcftor meb BG, og gooe tillige igjennem S og T; bet ^Mon<br />

DG, fom berveb op|toaer, beler fonlcbesS tilligemeb MQ og NK<br />

Q}nrnlleleptpebet i to ^nrnaelepipeber HS eg SF eg 4 trefibebe<br />

•primmer, EITD, MTGS, TKGS og ELTQ.


II<br />

§. 32- £tti'cf. So'ggcS igjennem Singonnterne nf to<br />

mobfrnocnbc (^i^ol7.•|^cr i et 'Pnrnllelcpipcbon et "plan, foo<br />

belcr bet 'Pnra(tclcpipl•^ct i to ligctlorc trefibebe ^riimer.<br />

S5co. Cr 'Parnllclcpipcbct ret, bo ere be trefibebe<br />

^ri^mcr congrucnte; cr bet berimob jTjffvt, font EB, fnn<br />

bed bet ftr|t i 4 congrucnte 'Parnllolepipcber (§. 31); beleS<br />

be to 'Parnllclcpipcbcr, fvei-(;;jc!inan Siagonalevne gnne, otter<br />

t 4 Sdc, eg beici ciiboibcre nf biffe ^arnllelcpipcbcr be to,<br />

igjennem f)vilfc Singonnlcn goacr, foo opftnne otter 4 ni;e<br />

^'^arnlfclcpipcbcr, 0. f. v. SScb fnnlcbcg at fortfffttc Selingeit<br />

vi'dc ber opftnne pnn ben cue ©ibe en 93i(tngbe ^nrollelept;<br />

pebcr, og til bi|Te finbeS tilfonreiibe pnn ben nnben ©ibe,<br />

tillige blioer en ^Diongbe fmno trefibebe Q)ri«mer; men biffe<br />

funne oeb fortfnt Seling blive fnn fmooe, at be olbelcg for;<br />

fvinbe; og oltfnn fnnlcbeg begge ©ti;ffer nf 'porallclcpipebet<br />

ligeftore, eller bnte beelt t to Uge(tore Sclc.<br />

§. 33- £ ir rcf. trefibebe 'Pri»mcr poo fomme ©runb;<br />

flnbe, mellem fnmme pnrnllclle ploncr, ere ligeftore.<br />

95et). 5cgncg til ©runbfloben bet tilfvorenbc ^oral;<br />

lelogrom, fao lobe to ^oroHelepipebcr fig tcgne, fom ibet be<br />

(iooe pno fomme ©runbflobe, mellem fomme porollelle QJlo;<br />

ncr, ere ligeftore (§. 30), men of biffe cr bet jpaloe igjen<br />

be opgivne trefibebe 'Pri»mer (§. 32), nltfao biffe ligeftore.<br />

£tl(. I. So fleerfibcbc ^ri^mcr »eb nt bele ©runb;<br />

finbecne t 5riongler og igjennem Singcnnlerne nt tegge ^In;<br />

ncr ftebfe lobe fig bcle i trefibebe, inbfeeS, nt ogfnn fleer;<br />

ftbebe 'Primmer ere ligejlore, nnor be flooe poo fomme ©runb;<br />

flaber.<br />

Si If. 2. S^ave to 'Primmer fnmme jp^ibe a; fomme<br />

lobrette Jffjinnbe mellem ©runbfinbcrne, og @runbf!nbcrne


12<br />

tillige ere congrucnte, ba Inbe 'prigmerne (Tg ^enfere poo<br />

fomme ©runbftobe og bringe imellem fomme porollelle 'Plo;<br />

ncr; be ere oltfno ligcflore.<br />

J. 34. £


13<br />

vcb D, fnn ot E'DG = PLM, og fulbfcrtcS 'Porallclcpipebet<br />

DP.', bo noor CG betrogteS fom ©runbflobe, er 'Porollel. DB'<br />

=z= DB (§. 30). Xjenfm-cij oltfoo DB' i ©tillingcn SY, fnn;<br />

Icbcg ot -MS liiiiKr i en ret Sinie meb MN, bn liggcr ogfnn<br />

i\ro i atetningen nf LM; fortengcg nu 'Plnncrne RK, LN, PR<br />

og XU, fnn opftnner 'Pnrallelepipebet MZ. 9^u er LPi: MZ<br />

=z LAI: MU og RIZ : SY =z MN: MS (§. 34). 2(ltfnn<br />

LR : SY =: LM X MN : MS X MU; men bo efter 7int<br />

togclfen EG = LN og EG == E'G = MT, foo er<br />

LN = aiT, og felgcligcn LM: MS = MU : MN (L §. 124<br />

5111. 1). 3tlt)"ao LM X MN = MS X MU eOcr LR =: SY;<br />

men SV = DB' = DB, oltfnn LR = DB.<br />

S111, 'trefibebe Q>rigmer of fnmme ^sibe paa lige;<br />

(lore ©runbfinber ere ligeftore.<br />

§' 36. Op3. 3tt fotvnnble fivilfctfom^elft firefibct<br />

*Prilme til et trefibet.<br />

Opf. Snb ©runbpnben of bet giwne ^rigme vffce<br />

ABCD; brog Siogonnlen BD; igjennem C brag CG =fc BD<br />

eg trojf BG, foo er ABDG = CDG (I. §. 70); conftrue;<br />

reg nu ligelebeg i ben onben ©lunbflabe et 'Jrinngel, ecng;<br />

liggenbc meb BDG, og igjennem BG og ben t ben pvcrfte<br />

©runbflnbe til ben funrcnbe Sinie ct 'pinn teggeg, og ^Mnnct<br />

igjennem AD foctengeS, fnn opfrnner et trefibet 'PriSme poo<br />

BDG ligcftort meb 'Ptigmet pnn BCD (§. 35 "Sill.), oltfno<br />

nnnr 'priSmet pno ABD foieS til, er^olbeS 'Prigmet poo ABG<br />

ligeftort meb 'Pri^met pno BCD.<br />

Sill. Sigelebeg fnn et^vcrt fenifibet 'pri^me fotvanb;<br />

leg til et fiirfibct; bette otter til et trefibet, ligclebcS et fejc;<br />

fibet 0. f. v.


14<br />

§. 37* £«l'Cf. ©tone to ,'Prigmer pnn ligeftore<br />

©runbfinber og l)ave fomme Jpeiber, bo ere be ligeftore.<br />

Set). 95cgge Q3rigmer funne forvonblcg til trefibebe,<br />

f)\)ig ©runbfinber ere ligeftore meb be epgiune 'Prigmerg, og<br />

nltfan inbbi;rbeg ligeftore (§. 36). 93^en bn tiUigc g^rigmcr;<br />

neg jjaibcr ere ligeftore, foo blive biffe ligeftore (§. 35 5'ltO<br />

§. 38. £(Ercf. 'Prigmcr, fom ^nve ligeftore Jj«i;<br />

ber, for^olbe jig fom bcreg forfrjellige GrunbJTfnbcr.<br />

Set). S3ion forvonbler 'Prigmerne ferft til trefibebe,<br />

og bernaft forbobblcr bem, fnn ot be 61i»e 'Porollelepipeber;<br />

ere biffe nu iffe rette og bereg Grunbflober ligcvinflebe, fno<br />

funne be bringeg bertil, og ben fomme Sonftruction foretogeg<br />

fow §• 35* 9^u et ligefom for^en 'Pnrnllelep. LPi : MZ<br />

= LM : MU og 'Pnrnllelep. MZ : MY = RIN : MS, nit;<br />

fnn 'Pnrnllelep. LR : SY = (LM : MU) + (MN : M.s);<br />

men ©runbfinbcrne LN og SU for^olbc fig ogfnn fom (LM : MU)<br />

4- (MN : MS), nitfno spovnllelep. LR : SV = LN : SU;<br />

men 'Pnrotlelep. LFi cr bet Sobbclte of bet ene nf be 3i»ne<br />

prigmcr, 'Pnrnllelep. SY = DB ligeftort meb bet Sobbeltc<br />

of bet nnbct givne "Prigme, ligelebeg er LN og SU = DF<br />

bet Sobbeltc nf be giuiie 'Prigmcrg ©runbflobe. 3lltfoo for;<br />

f)olbe prigmerne fig fom ©runbffnber.<br />

§. 39. £


15<br />

= GHIKL (§. 37); men DFEC : DEFY = QR : RY,<br />

oltfnn og DFEC : CIIIKM =zz QR : ST.<br />

§. 40. £ tt r e f. 'Pcigmcr ftnoe i fommcnf'at Sor^olb<br />

of ©runbflnberne og jjoibecne.<br />

Set). 'Jcgn ct 'Prigmc, fom ^nr ij^ibe tilffftlebg meb<br />

bet ene givne, ©runbflnbe meb bet nnbct. Scttc fov^olber<br />

(ig nitfno til bet ene giime, fom be giune "Prigmcrg Jj^iber;<br />

til bet nnbct fom 'Pvigmerneg ©runbfinber, oltfoo flnne be<br />

givne 'Piignier i fammcnfnt gor^olb nf ©runbflaber 03<br />

jjeibcr.<br />

St If. Sre ©runbfinber og J^eibcr reciprcft proper;<br />

tionnle, bo ere Q3rigmernr ligeftore, og omvcnbt.<br />

§. 41. £


i6<br />

fober; tilli3e ere ^t\c\inatmi t^inticme eeng i beggc 'Pyra;<br />

miber; biffe oltfnn consruente.<br />

5


I?<br />

tti oltfoa oHe 'Prigmcc of ben ene ^i;romibe 03 liselcbcg of<br />

ben nnben, fan ville biffe ©ummer for^olbe pQ fom "ppo;<br />

miberneg ©runbflober. tOJen biffe ©ummer funne bctrogteg<br />

fom ^»;comibernc.fel»; oltfao for^olbe ^i;comiberne fig fom<br />

bereg ©runbfinber.<br />

S «I f. Q>i;rnmiber pno ligeftore ©runb(lobcr 03 meb<br />

ligeftore Jj0ibct ere ligeftore.<br />

§.43. £ <br />

^olb of ©runbflaberne 03 ijaibcrne.<br />

Sev. '?e3n til 'Pi;romibctne be tilfvorenbe "Prigmcr,<br />

biffe ville bcpolbe ^i;romibcrneg ©runbflober og ^ove jjaibcr<br />

f«llebg meb bem; "Prigmerne (laoe « fommenfnt gor^olb nf<br />

u. 2


©runbfinbcrne eg jj0ibcrne, fnnlebeg ogfnn 'Jrebicpnrtctne af<br />

bem eller "Pyrnmiberuf.<br />

S111. Sec to '•pyrnmibcr ligeftore, be. ere bereg ©runb;<br />

flnbc: og S^sibev reciproft picpcrtion.ile og oravcnbt.<br />

$.45. £ « r e f. ^ijareg i en trcf'tbct 'pprnmibc ct<br />

©nit pnrnlldt meb ©runbfinben, bn cr bette ligcbnnt mti<br />

ben, og ben offToorne "Poromibe er til ben l)de i triplicccet<br />

Sor^olb of ijaiberne.<br />

Set). "Pyramiben vffre AEFG, ©nittct BCD. ^<br />

erBDqfcEF, altfno AE:ABz= EF: ED, ligelebeg BC ah EG,<br />

nitfnn AE: AB ^ EG: GC; felgdigen EF: BD := EG : BC;<br />

ligelebeg EF ; BD = FG : DG, nltf.ia A BDC o EFG.<br />

aicn nu for^olbe ftg "Pi;r. AEFG : ABDG = (AI: AH)<br />

-|- (A EFG: BDC) (§. 44). ^Tun EFG: EDC = 2 (FG: DC);<br />

J G : DC = AF : AD eg AF : AD = AI : AH; nit,<br />

fnn A EFG : BDG = 2 (AI: All) eller "Pvr. AEFG : ABCD<br />

=z 3(AI: AH).<br />

Sill, ©cttningen gjcrlbcr 03 for ficerftbebe 'Pi;rnnti;<br />

ber, i bet biffe Inbe fig bde t rteftbebe.<br />

§. 46. % i I. Sreier et Stectnngd fig om (In cm<br />

©ibe, inbtil ben erl)olbcr fin farfte ©tilling, f"no folbcg bet<br />

Scgeme, fom bcvveb opftnncr, en (Ei;linber.<br />

(in €i;linber begranbfcg nltfan nf to pnrollelle dirfler,<br />

fom fnlbcg bcng ©runbpnber, eg en fvum ^Inbe, ber cnbet<br />

fig iib biffe iSirflerg 'Pcrip^cvier; forbinbcg ©runbflnberncS<br />

;£cntcr nicb en ret Sinie, bo fnlbcg benne eiilinbereng 3(]ccl.<br />

3 bcii bcfinercbe £i;linber bliver tRcctnnglctg fnftliggcnbc ©ibe<br />

;Xrc!, bcn-.c ftnncr lobret pno ©runbflnberne, ^i;linbereii falf<br />

beg bcvfbr ret; ^nvco berimob en dvlinbcr, hn-n 'Vivien cr


19<br />

unbcr e.n onben SSinfel enb ben xfttt inclinerct mob ©runb;<br />

flnbcn, bn fnlbcg ben ffjofv.<br />

S i n. I. fin £i;linber fnn betrogteg fom et prigme,<br />

f)vi^ ©runbflobe cr en reguter 'Polpson of ucnbcli3 monse<br />

©iber.<br />

Si If. 2. Sn fFj«v £i)linber bliver ligcftor meb en<br />

ret paa fomme ©runbflobe og meb fomme S^eibe (§, 37).<br />

S i n. 3. £i;linbre ftooe i fommenfot Sor^olb of ©runb;<br />

flober og ijaiber (§. 40); men, bo ©runbflnberne ere S:irflcr,<br />

og biffe ftnoe i bupliccret gor^olb of Siometrcrnc eller Slobierne<br />

(L §. 130. 5ill. 3), foo (tooe Svlinbrerne t fommenfot Sot;<br />

^olb of Sor^olbet mellem .^aiberne 03 bet buplicerebe gor^olb<br />

mellem ©runbflobcrneg Stabler cller Siomctre.<br />

21 n tn. en fljao gplinber ligcfaaocl fom en ret fan og:<br />

faa tcenteg fremtommcn, naar en Sirfel beoagcr fig iii)<br />

af fit qjlan, flebfe paraUel meb fig felo, mebeng at gent:<br />

rnni befTvioer en ret 2inie, fom bn blioer Solinbereng<br />

3iicl.<br />

§. 47. S f'. Sreier et retvinflet ^rionsel fi3 om<br />

(in ene Sot^ete, inbtil ben er^olber (in farfte ©tillins, foo<br />

opftooer bcrveb et Se3eme, fom folbeg en ^ e g I e (conus).<br />

Sn Scgle begr


20<br />

©iber; ben er oltfoo ligcftor meb Srebieporfen of en £i;Iim<br />

ber poo fomme ©runbflobe og of fomme S^sibe.<br />

S t n. 2. .Segler ftooe i fammenfot gor^olb nf ©runb;<br />

flober eg i?»iber, eller i et S')i'f)olb fommenfot of i"p0iber;<br />

neg Ser^olb 03 bet [buplicerebe gor^elb nf ©runbfloberncg<br />

SRobiet eller Siomctre.<br />

§. 48. S f '• Steier en jjolvcirfcl (ig om fin Sia;<br />

meter inbtil ben er^olber fin f^rfte ©tilling, fno er bet £c;<br />

flcmc, fom bcrveb opftooer, en ^ugle (spliKra),<br />

3(Ufao cr en ^ugle et Scgeme, begrffnbf'ct of en enefle<br />

frum Overflnbe, i ^vilfen ^vert ^>unct er ligclongt borte fro<br />

eet ^unct inbcnfor OverfTnben, fom fnlbcg Centrum.<br />

§. 49. £ (V r c f. OverjTj«reg en .Kugle of et QMon,<br />

bo er ©nittct en Sirfel.<br />

Set). 5


21<br />

§. 50. S f f- ^t regutert Scgeme er bet, ber pnn<br />

one ©iber inbeflutteg of ligeftore rcgulo-re 'plnn;5igurcr.<br />

So nlle 2?inflcrne t eet Jpfarne tilf'nmmcn ffuUc ubgjeve<br />

minbre enb 4 R (§. 27), fnn ere felgcnbe vegutere Segemer<br />

fun mulige:<br />

I. 95cgr«nbfcbe of ligefibebe 'Srinngler:<br />

a) ? e t r 0 e b r e t, begranbfct of 4 ligefibebe Sri;<br />

angler; bet f)nr trefibebe Jjijarner.<br />

b) Octnebret, bcgrtfnbfct of 8 ligejibcb: 5rinng«<br />

ler; bet ^nr firefibcbe Jjjorner.<br />

c) 3cofnebr''t, begro'nbfet nf 20 ligefibebe Iris<br />

ongler; bet ^or femflbcbe Jpjerncr.<br />

2) SSegrcenbfcbc of avobroter:<br />

d) jperoebret, of 6 Clvnbroter; bet ^nr trefibcl*<br />

ijjBrner.<br />

3) SBegrffubfebe nf $5emfnnter:<br />

e) Sobecocbret, of 12 rcgutere S


22<br />

fnnbotttje Sele; berimob efter Secimol; ?!Raolct foocr ©ibc;<br />

linictt lo Sele 03 Cubug felv 1000 SelCi 3(ltfoa bo i cub'<br />

€r ttse i 6e35e 3nbbelin3er, cr<br />

Secimol Suebec.<br />

1726 cub" : 1000 cub"<br />

I cub' I cub'<br />

1000 cub" : 1728 cub"<br />

lOOOOOO cub"' ^=. 3985984 cub'"<br />

veb fpilfen 'Jnbel bet ene S)tonl let forvonble* til bet onbet.<br />

§. 52. £


2'\<br />

21 tint. Sor at nbmaale dolinbre, bcticiiev man fig i -^lU<br />

miubdigbcb af eii 9i it be ft 1.1 f (vii;;iii.i pitlionuti-icn).<br />

Senile cr inbrcttet \^aA folgcnbe ffliaabc: SDlan ralgcr<br />

fom fflfaalc:trciil)cb en h-riaut (Jrlinbcr, f. Gr. ct ^pcttc;<br />

iiiaal, afbelcr ben ene £ibc af en gitaalcftoE i 7>de (igeflore<br />

meb .(>8ibcn af ben gii^re (Jolinbcr; pan ben a>i:<br />

bon £i?e ai'fsttcg 1) (Siilinbcrcng 2i>imetcr, 2) ©iben<br />

i et Grabvat ber cr bol'bdt, 3) tectioKHit, 4) fiivbob:<br />

belt, 0. f. V. fan |loit fom J^iamctvciui Qvabrat; meb ben<br />

fovfte Sibc maaleg ben nbctie; btc giilniDevg S>mic, meb<br />

ben anben t'.'ng (SriinbflaJc; Xnllciie, fom lietseb nb;<br />

fomme, angioe, mnUipliccvctc meb l;iuanbcn, Ijvijvmange<br />

spettcr gpli.ri'cven inbc[)oli>cv.<br />

I^c fiiir, lu'cri i SllminbcIigt'Cb flrbenbc l^u'c irbc-=<br />

f)olbeg, \)A


24<br />

^vlg J?0ibe vor x, foo 6lev ben nffortebe Jtcgle SorfTjeHctt<br />

tnellcm ^ele Seglen 03 benne minbre, ellcr<br />

iR'(a4-x)a- —ir'xar<br />

«Ken<br />

R : r = a-f-x: X<br />

Qlltfoo<br />

R — r:r = a:r<br />

^erof<br />

ar<br />

~ R —r<br />

g^lscligen ben offortebc ^egle<br />

aR ar<br />

1 TtJ _. 1 ..i —<br />

•3-tv R—r — ?r — -j-r • R—r<br />

Caer<br />

R' —r?<br />

^ _ aT == i(R=+Rr + r*)aT;<br />

R — r<br />

2t n m. ®ennc gormel finber megen 8ln»enbelfe t bet<br />

spvactifle, i bet flere .Sar, fom (sEjwpper u., ere affor*<br />

teie .Segler. Dgfaa Ijule 2Ketab Jobber ere i Sllminbes<br />

ligljeb gorfljellen imellem to afEortebe Segler. Otogen:<br />

lunbe lige SroJitammet lobe fig egfaa teregne fom nftor*<br />

tebe .Segler.<br />

§. 55. Overfloben nf Sesemet, bet 6egr«nbfeg nf ^lo;<br />

ncr, finbeg let, vibe, ^vtg


25<br />

©runblinte vnr Ci;linbcteng ©runbffnbcg "Peripherie; ben er<br />

nitfnn ligcftor meb dh;r; foge vi nitfno cn '33iellem;'Propor;<br />

tional; Sinie mellem d og h, og meb benne fom Sinbiug be;<br />

fFrive en Cirfd, ba bliver benne Civfd liig Cijlinbcrcn*<br />

©verflnbe.<br />

Cn "Pi^rnmibeg ©itcflnbcr ere ?vinngl?r, og beregncg<br />

oltfnn efter L §. 144 lill. Seieg ^crtil ©runbflabcn, ba<br />

^nveg f)de 'Pprnmibeng Oociftnbe.<br />

Cn ret Segleg frumme Overflnbe funne vt ttrnfe eg fom;<br />

menfot of en 3»«ffc of fmaae ^riangler, f)vig ©runblinicr<br />

tilfommen ubgjarc ©runbflabeng 'Peripherie, jjeiben ben fan;<br />

fnlbte ©ibdinie i ^eglcn 3: en ret Sinie fro ^oppunctet neb til<br />

©vunbflnbeng ^erip^erie; fnlbcg benne I, fno cr Ovcrflnbcn<br />

•J^dlr eller rl^; vnr 1 iffe given, fnnbteg ben let liig Y^r'-f-'^"*<br />

SSi funne og gjcnnem Conflruction finbe Segleng Ovcrffabe,<br />

i bet vi fogte en 93iCllem;'Proportionnl;Sinie imellem r og 1,<br />

eg meb benne fom Sinbiug befTrev en Cirfd.<br />

Cn offortet Scgleg frumme Overflnbe er ligcftor meb-<br />

et 'PornUel;'5rnpc5ium, ^vig pnrnllclle ©iber ere be to Cirf;<br />

lerg "Peripherie, Jjeiben ligelebeg en ©ibdinie, fom vt ville<br />

Bctegne meb s, altfno er ben ligcftor meb (R -j- r) s z--<br />

Cr s iffe given, bo finbeg ben liig Y-->'~{-{K — r)-.<br />

§. 56. £ (B r c f. Cn .^olvfuglcg 3nb^olb er | of en<br />

Ci)linbcr, l;vig ©runbflobe er .Sujlcng ©tcrcirfcl, og f;vi«<br />

Jjaibc er .^ugleng Stnbiug.<br />

Set). 'Strnfe vi og en Cvabrnt ABCD, en O^va:<br />

brnnt ABC, et ligcbenet jetvinflet ^linugcl ABD, olle nt<br />

breie ftg om ben fa:ltcbg ©ibe AB, bo beffriver 0.vnbvntet<br />

Ci;linbcrcn FHDEC, Q.vabrnntcn .^nlvfugleu AEGC, Zxix^p


26<br />

let ^eglen FHDB. Sffggcg nu igjutnem O ct ©nit lobret<br />

pno^AB, bo gjennemjTjffrcr bet olle tre Segemer t Cittlcr,<br />

ncmlig Ci)linbcrcng befTrevcn meb Slobiug OL, .Kugleng meb<br />

SRobiug OK, ^cgleng meb Stobiug OL Srngcg frn B til K<br />

en ret Sinie BK, fnn er BK» = BO" + OK' eOer OK'<br />

= BK^ —BO'; men BK = BC = OL, bn A OBI<br />

(^ ADB og bette et ligebenet ?rinngel, er ogfnn 01 = EO,<br />

oltfoo OK* = OL' — OI=; multiplicercg ^eelt igjennem<br />

meb Collet s-, erf)olbeg OKV == OLV —OIV, cL'cr<br />

Cirflen i ^uglen ligcftor meb Cirflen of Ci^linberen, minbre<br />

enb Cirflen nf ^eglen. Scclteg nu AB i uenbelig mange<br />

Sele, eg fnnlebeg uenbelig mniigc ©nit Ingbcg, ville .Kugle;<br />

©nittene nlle vcere ligeftore meb Ci;linbcr;@nittene, minbre<br />

enb ^eglc;©nittene, eller ijnlvfuglcn vtrre ligcftor meb Ct;;<br />

finbcrcn, minbre enb ^eglen; men ^cglcn er ^ of Cylinbe;<br />

ven (§. 53 ^ill.)/ nltfao jjolvfuglen •§• nf Ct;linbcren.<br />

S11 f. I. Ubtn;ffe vi Ci;linbercn veb gormlen (§. 52<br />

5tll. 3), fnn, bo jpeibcrt i ben er r = ^d, er bcng 3"b;<br />

^olb -^d'T, Jjnlvfuglcng oltfnn TT^'r; i?eel!uglcn er falgc;<br />

ligen ^ernf bet Sobbelte, ellcr -J-d'n-. SSilbe vi fcrtte 9Ia;<br />

biug inb t bette Ubtn;f, bo blcv ^ugleng cubiffe 3nbfiolb<br />

S i f f. 2. SSnr 3nb^olben given ligcftor meb C, fnn<br />

fonbteS<br />

V 6G<br />

4~


27<br />

Sill. 3- ^nb^clbet nf et ^ugleregment ANOK fin;<br />

beg veb frn Ci;linberen FD'L nt tvo-fte ben nffortebe .S^cgle<br />

FHDIM. Snb ben for bi'Tc £;r,cmer fallcbg S^eibe AO<br />

vorre a, fnn cr Ci;linbcrcu ai'^-, Scglcn ^ a-, ^vor<br />

V — p<br />

p =: OI = OB zzz: r — a, oltfnn ©cgmciitet<br />

r'-(r-a)3<br />

r — (r — a)<br />

= ar' s- — 4. (,-3 _ (r _ a)3) ^<br />

r ai"*jr — (i" a — r"*" -|- 3 a')3-<br />

=^^r — ia)a=3-<br />

St 11. 4. Sugle;©ectoren, fom epftob nnnr cn<br />

Cirfd;©ector ABK breiebe fig om, fnnbteg, nnnr til<br />

©egmentet logbeg ^eglen, ber opfom veb OBK'g Ombrci;<br />

ning. Stobiug for 9&nfig OK er !01ellemproportionnl; Sinie<br />

mellem beggc Siometreng ©ti^ffer (L §. 118), b. e. mellem<br />

a 03 2r — a, oltfflo OK' = a (2r — a), foilgcltgen Seglctt<br />

= •J-a(2r — a)(r — a)^; i bCt Jp0ibcn OB =: r — a;<br />

cller ogfao ^eglen farV — a'rjr + iaV. gijicg ^evtfl<br />

©egmentet := raV — i^^Tr, erl;olbeg for ©ectorcn Ubi<br />

tci;ffet far'77, ^vor a ligefom fortjen beti;bfr S^mben of bet<br />

til ©ectorcn fvorenbe ©egmcnt.<br />

Sill. 5. Cnbnu f)ar mnn nt tegge 5li«rfe til be<br />

fileformcbe ©cctorcr eller Sole of Seglcn, fom inbeflutteg<br />

mdlcm to ©tor; Cirf ler. Cr S^fl'^ntionen nf biffe ©tor;<br />

Cirf ler given i ©robcr, bn iubfeeg let, ot ^uglcn forf^olbcr<br />

(ig til cn fanbnn ©ector, fom 360" til bette ©vabe; 3tntn!;<br />

tiler fnlb ©rnberneg 2lntnl n, fnn er ©ectorcn<br />

n<br />

360° '^ "


28<br />

§.57' OP3« ^' P"^« glnbe;3nbf)0lbet nf ^ugs<br />

leng Overflobc.<br />

Op I. og Set), gorcjtille vt og et Clement of ^ug;<br />

leng Overflobe, bn er bette at betrogte fom en ret offortet<br />

iieglcg Overflnbe, ^vilfen fnn finbeg (§. 55), noor ©ummen<br />

nf giobicrne multiplicercg meb ©iben og Collet jr; ontogeS<br />

oltfnn ct ©nit MM' sjort igiennem ^unctet P eg ucnbdigt<br />

jiffr bcrveb, men ligelnnst borte pnn ^e33e ©iberne ©nittene<br />

mm' 03 fiifi' logte, fon er .Sugle;Clementetg Overflnbe 2PM<br />

X/otm Xsr. ^^crt bo ^m cr uenbelig lille, moo ben be;<br />

tro3teg fom cn Seel of '5:nngentcrt MT; f*Ibeg fi;n m neb pn«<br />

fifi' ^erpenbicuteren mN, fnn er A mN^


29<br />

Siabing, og fom corrcfponbcre meb Doerflabcng Sele,<br />

faa, ba alle biffe ^cgler baoe ftsUcbg .^^e'De, labe be fig<br />

abbcte, og bcteguee Cvcrflabcn af ^itgien meb S, faa cr<br />

©nmrnen af bem cller ^^iiglcng Oi'bbclb |rXS, IjoiU<br />

fen Sormel nbtrpEfer Sotbinbclfcn mdlcm Oociflabe 09<br />

3nbbolb af ^iiglen.<br />

§. 58. S3cb Xjjfflp nf be nnfeirte gormler Inbe nu forfFjd;<br />

lige ftereometriffc gorvnnblingcr fig nrit^metifft<br />

ubfere, t bet vi gjcnnem 3legning funne finbe be ©ti;ffer,<br />

fom fi;lbeftgj0ve en Opgnve om, at forvonblc et i 3nb^oll><br />

opgivct Scgcne, til ct nnbct of en bcftcmt ©fiffclfe. gee<br />

foovibt ^cri forefomme Ubtn;f, fom ifalge I. §. 154 lobe (ig<br />

conftruere, fan benne gorvonbling og jTee geometrifft.<br />

§. 59. Op3. 2(t forvonblc en ^egle, ^vig Simeiu<br />

(ioner ere givne til en Ci;Iinber, nf en given S^aibe.<br />

Opi. ^egleng Xjeibe vace a, bcng Stnmeter d, fno<br />

er -jSj-adV llbtri;ffct for bcng 3nbI)olb; Cplinbcreng fegte<br />

Sinmcter varre x, beng givne j?0ibe h, fnn er bcng 3nb^olb<br />

I hx-s-; l)er er tut C!)linber og .Scgle ligeftore, altfno<br />

oltfao<br />

Jyad's- := ihx=5r, ellcr 4-ad' = hx',<br />

= \A'<br />

' ad^<br />

3h<br />

Scttc llbtrijf Inbcr fig conftruere, veb ferft ot fege cn<br />

^ ad<br />

©terrclfe m, fonlcbcg ot 3h:a d: m; bo m —r- —<br />

3l»<br />

og bern(E|t f»gc x fonlcbcg ot mix = x: d.<br />

§. 60. O p 9. "iit forunnble ben i)de Overflobe of<br />

c:: ret .Segic, hvii Simcnfionei- eve f.fjcntte til cn Cirfd.<br />

O p i. Sinmetren vffre d, j';'C'ibr;i h, fnn cr ben<br />

f.'rinnie 0';?cvpab{ lifcft-v; ircb -', d :r Yid^-f-ir- (J. 55),


30<br />

SJnfiiS er { d' TT, oltfoo f;elc Overfloben liig i d 3- V^^d' + h*<br />

-f 4- d' a- = i d (.Vi d' + b' + > d) 3-. ©£i3eg nu en<br />

5)tellempropottional;©te'rrelfe imellem 4-d 03 V-J-d' + h'<br />

-j- Jd, bo bliver benne 9?abiug i ben forlongte Cirfel.<br />

Itbtryftet lober (ig let conftruere.<br />

§. 61. Opg. 2lt finbe ©tbelinictt i en 5


- --n-iwi-«


32<br />

§. 3' 2)n vi vibe, nt i bet retvinfle&c ^riougel (tebfe<br />

h' = a'-fb'<br />

fan er<br />

ellec<br />

Sigelebeg<br />

eller<br />

tillige<br />

cQec<br />

I =<br />

1) I =<br />

h'<br />

2) sec A' ;<br />

h'<br />

"? ^^ ^ + 7^<br />

3) cosec A'<br />

Cnbvtbere cr<br />

eller<br />

eller<br />

h<br />

b a<br />

4) sin A X cosec A —"" I<br />

b b<br />

= I<br />

bXb =<br />

sin A' -f- cos A'<br />

a'<br />

= tgA' + i<br />

. 1>*<br />

= I-f-cot A'<br />

= I<br />

5) cos AX sec A I<br />

Sivibcreg -- meb<br />

b a<br />

b T-/ bn er ftvotieiucn — cUcr<br />

" b<br />

sin A<br />

6) tsA =<br />

cos A<br />

-


33<br />

b a ^ b<br />

Sigdebeg, bivibereg — "'«'' T> ef avottcntcn — eUev<br />

b ft «<br />

cos A<br />

7) cotA =<br />

' ^ sin A<br />

a b<br />

^lUltipliccrcg — meb —, bo ec "Pcobuctet i ellet<br />

b a<br />

8) tg A cot A = I.<br />

flSeb Jpjfflp of biffe Signingct lobe, ttonr een tn'sotto*.<br />

ttietrijf ©t^rrelfe (gunction) for en SSinfel cr given, be »v;<br />

tige for fnmme SSinfel fis ublebe. g, Cjc, nnnr ©inug er<br />

given, bn finbeg Cofinug ifel3e i), Cefecong 03 ©econg if8l3e<br />

4) 03 5)/ 5ongeng 03 Cotongeng if^lge 6) 03 7).<br />

§. 3. SefTreveg fro ^oppunctet C of en SSinfel en<br />

€trfelbue, fno inbe^olbt ben et lige TCntnl ©rnber fom SSinf;<br />

len, og berfor funbe be tti3onometrtfFe ©tarrdfer (guncties<br />

Iter) e3fafl onfeeg ot til^»re 95«cn. gfflbebcg fro B Q3er;<br />

penbicuteren BD, bo vor<br />

BD<br />

— =:= sin AGB = sin AB<br />

BC<br />

Opretfeg fro C en Sinie CE J_AC, foo «bfi;lber/;_ BCK<br />

ben sivne SSinfd til 90", 03 li3elebeg SSucn BE ben givne<br />

93ue AB til 90° eller er Complement til ben. 3 ^rionglet<br />

BFC er nu<br />

BF<br />

— = sInBCF = sin BE<br />

BC<br />

men BF = DC, oltfno<br />

DC<br />

•— = suiBCF = sin BE<br />

BC<br />

£= cosDCB = cosAB<br />

n. 3


34<br />

g^Igdigen er nlminbeltgett<br />

cos X • sin (90" — x).<br />

Srogeg fro A en '?on3ent, 03 BC fortengeg til ben<br />

tr«|fer ben i T, foo, bo t AATC^ BD ec ^rongvcrfol, er<br />

AT : AC = BD •. DG<br />

03<br />

nltfao<br />

09<br />

5;,.<br />

b. e.<br />

nifc<br />

TC: AC = BC: DG<br />

AT BD<br />

AG DC<br />

TC *^ EC<br />

AC DC<br />

AT<br />

= tg ACB = tg AB<br />

AG<br />

TC<br />

^ "<br />

•— sec ACB = sec A<br />

Sigclebeg, ^vig fro E bro3eg til S en 5:on3ent vor<br />

SE BF DC<br />

== -^— = == cot ACB = cot AB<br />

EC FC BD<br />

SG BC BC<br />

— cosec AGB cosec AB<br />

EC FC BD<br />

Set inbfecg, ot cot ACB == tgBCE, eg ot cosec ACB<br />

= secBGE, eller Ot olminbdisen<br />

cot X — tg (90° — x)<br />

cosec x sec (90° — x)<br />

3fntoge vt nu Slobiug fom Cen^eb, foo vilbe, ^vi« vi<br />

meb bet 3}iofll ubmnnlte allevesne,, BD ubtrt;ffe ©inug, BF


3.5<br />

eller DC Coftnug, AT 5angeng, TC ©econg, SE Cotongcng,<br />

SG Cofecong for SSinf len ACB eller SBucn AB.<br />

91 n m. Sotbi fa«Icbc« Sinierne ubmaaltc meb Dlabiug fom<br />

Gcnbeb ubtrotfe be trigonomctrif?e Sttnctioner, EalOcu<br />

man fabuanligen Sinierne felv ©inug, Xangcng u., i«<br />

fell) benne SBcndonclfe anucnbcg, om iltabiug iEEe oar<br />

Genljeb, og man Ealbfe bcm ba ©inng, "iangcng ic,<br />

unbcr gorubfottning af en anben bcftcmt SHabing. 2)iffe<br />

UbtrijE eve itegentlige; tl)i ba >H'nfigtcn af Srigonomc:<br />

tricn cr SRcgning, maae alle ®t«rrelfer ben bctragteg<br />

fom lal. 3niiblertib letter ben Joreftillinggmaabe, fcrnb:<br />

fat at intet falfl SSibegreb bcrmeb forlnnbcg, ftnnOem<br />

3nbfigten af flere trtgcnomctrifle ©cetningcr, fom bett<br />

ogfaa tjener til at fatte be iftsr oelbve eiriftcr, ber be:<br />

tjene fig af ben.<br />

sRaonct Sinus er enten opitaaet af bet SatinfTc, ibet<br />

en ginug cr fflJaal for en S3ue (sinus), og gioeg beg:<br />

aarfag famme SenoiDnelfe, cQcr og af semissis iuscriptaj<br />

(^alobelcn af eijorben, (Ircoen forEoriet S. Ins.)<br />

§. 4. .betrogte vi SSinf len, ibet ben gaoer over i on;<br />

bre Qvobranter, fao, for ot ^ove en geomctrifT goreftillin3<br />

of be trigonometriffe guuctioner, lober eg meb Siobiug i<br />

beffrive en Cirfel, i ^vig Centrum SSinflcng 2;oppunct lig;<br />

ger, bo blive be trigonometrifTe gunctioner Sinier, og vi ville<br />

nntnge bcreg SScliggcn^eb i ferfle O,vobrnnt for pofitiv.<br />

3(ntnge vt nu, at SSinflcn foreigeg meb 90°, ibet SBcnct<br />

AC bevcrgcr fig inbtil A', fan inbfecg, at bo A ADC ^<br />

A'D'C, A'D' = DC, D'C = AD; ligelebeg er CB-T'<br />

S: SEC, nltfan = ES; CT' z=: GS; cnbvibere cr CES'<br />

^ CBT; oltfao ES' = BT; GS' = CT.<br />

galgdigcn sin BCA' = cos BCA; cos BCA' =z=<br />

sin BCA; tgBGA' = cot BCA; sec BCA' = cosec BCA ;<br />

eot BCA' = tg BCA; cosec BCA' = sec BCA; eUcr iftc;<br />

3*


36<br />

bet for ot toge be trigonometrifFe gunctioner til ctt SSinfel<br />

i nnben dvobront, traffeg 90" berfro, og berpon f^geg<br />

olle gunctionerne til benne SSinfdg Complement. Jjvob<br />

^egnet berimob onsooer, bo er ©inug truffcn fro oven of<br />

neb efter, nitfno fom for^cn pofitiv; Cofinug berimob fto<br />

C til D', oltfao ( mobfot 9lctnin3 of Cofinug i ferfte 0.va;<br />

bront, fel3eli3en nesotiv, ^onseng BT' frn oven neb cfter,<br />

oltfoo ne3ativ, Cetnnseng fro E til S', nitfno nesotiv. ©e;<br />

cnng 03 Cofecong rette ft3 (tebfe meb jpenfi)n til ^egn efter<br />

Cofinug og ©inug, bo be multiplicercbe bcrmeb fFullc frem;<br />

bringe ben pofitive Cen^cb (§.3, 4 03 5); ben fetfte ec<br />

oltfno ne3otiv, ben (ibfte pofitiv.<br />

3 treble dvobrnnt tn3cg ©inug 03 Cofinug nf A CD "A"<br />

^CDA, nltfoo ere be li3eftore meb fomme gunctioner i f^r;'<br />

(te Q.vobrant, men 6e3ge negotive. 'Jnngeng og ©ecnng tngcg<br />

fom i ferfle 0,vnbrnnt of A CTB, ben ferjte oltfoo pofitiv, ben<br />

nnben berimob retter (tg i 5egn efter Cofinug, oltfao nega;<br />

tiv; of A CSE togeg Cotongcng, fom er pofitiv, og Cofc;<br />

cnng, ber fom ©inug er negntiv.<br />

3 ficrbe 0.vnbrnnt t03eg ©inug og Cofinug of A CA'"<br />

P'" S CA'D'; ligelebeg ?ongeng og ©econg of CBT';<br />

Cotongcng eg Cofecong of GES'; oltfoo ^ovc ^r be trigo;<br />

nometrifTe gunctioner lige SSitrbier meb gunctionerne i onben<br />

Ctvflbrnnt; fung er ©inug 03 ^nngens, Cotnngeng 03 Co;<br />

fecong negative, Cofinug eg ©econg pofitive. 3llt bette inbe;<br />

folbeg i felgenbe label, ^vor x er en fornnberli3 SSinfel:<br />

sin X<br />

cos X<br />

tgx<br />

cot X<br />

sec X<br />

cosec X<br />

X — a<br />

sin a<br />

cos a<br />

• tga<br />

cot a<br />

sec a<br />

cosec a<br />

= lSo°-[-a X = 27o°-f-a


37<br />

^00 ©runb ^erof vilbe trigonoitietrtffe 'Jnbellcr, bereg;<br />

titbt inbtil 90°, vffre tilflro-ffelige, eller ba, noor en SBinfel<br />

er over 45°, beng gunctioner flebfe finbeg mdlcm Comple;<br />

mentetg, ber er unber 45°, foo be^eveg ^obellerne ene bcreg;<br />

nebc til benne Ubftrttfning.<br />

aicgningen meb Sogorit^mer onvenbeg ifofr t 'Srigono;<br />

metrien, begnnrfng ere iffe felve ©inug, Cofinug JC, men<br />

bereg Sogorit^mcr ^cnfotte, bo ©inug eg Cofinug ere flebfe<br />

egcntlige S&refcr, 5angenterne fro SSinflcn unbcr 45° ligele;<br />

beg, fao finbeg i ?abellerne bcrc^ £e3arit^mcrg becnbifTe<br />

Complement til 10, eller, fom mnn finber bet i 3llminbelig;<br />

^eb ubtri;ft, ?obellcrne ere beregnebe til en 9labiug, ^vig £0;<br />

gorit^mc er lo.<br />

©econtcrn* (tnbel let of Coflnuffccne, Cofeconterite of<br />

©inuffcrne, veb ot bivibcre i meb biffe, eller eg Sogoritl);<br />

merne of ©ecnnterne 03 Cofecnnterne veb ot tnge be becnbi;<br />

(fe Complementer til Cofinug og ©iitug, en Svegning, ber<br />

fan let Inbcr fig ubfere, ot fom ofteft ©ecanterne eg Cofecan;<br />

tcrne iffe finbeg i 5obellerne.<br />

21 nm. 3lf ZaieUet foruben be (L airitbm. §. 127) anf#rfe<br />

ere, nicb .^enfpn til ben ttigonometrijie 2)eel, cnbnu<br />

nt mttxtet<br />

TAYLOR'S logarithmical and trigonometrical tables<br />

to every second. 4°, fcercgncbe inbtil 7 3)ec.<br />

Siffe Sabeller, fom faalebeg gioe ©ccnnber, blirc i<br />

aSrugen nffijten lige faa Degoemme fom be Salanbifle til<br />

5 ®ecimaler fra SKinut til JKinut, ibet 3nterpolatio=<br />

nen for en «»et Olcgncr Ean forctagcg i .^ooebet; be<br />

gioe i Ijrcrt 'iilf«lbe en ac«iagtig(ieb inbtil nogle faa<br />

^nnbrebe Sele af ©ecnnber, naar tieitfigtgmtjtgfige<br />

Sormler anoenbeg og aiegningen ooeralt f»reg meb tiU<br />

ftrotEEelig £EarpI;eb.


38<br />

Stoeflen for alle 93cregninger vilbe ZavUt meb 6 lie:<br />

dnialer, fom oel onoenbte oilbe gioe SSinfler til cn<br />

Slccurateffe af ^ ©ecunb, gioe tilflraffelig g^eiagtigOeb,<br />

eg beregnebe fra lo til lo ©ecunber lige Sctljeb meb<br />

CRegningen meb Itaplor'g Sabeller. SDct er at tjoabe,<br />

at biffe, ber if«f for aiflroncmerne ere blconc cn Xrang,<br />

fnart ville ubEomnte.<br />

3 imangel af Xaplor'g gaoler er, Ijvor en f)»iexe<br />

®rab of Stoiagtigbeb fr«oeg, enb ben, 5 ®edmalcr Ean<br />

ffaffe, ncmlig 3" til 5", be CallctfEe til 7 ®eci:<br />

maler raeefc at anbefalc, formebclfl bereg Corrcct^eb 09<br />

frtig.<br />

§. 5. 97aor ©inug og Cofinug of to SSinfler, a og b,<br />

ere givne, bo ot finbe ©tnug 03 Cofinug til bereg ©um.<br />

?Beffrivcg meb Stnbiug lii3 i frn SSinflcrneg fffUebr<br />

^oppunct en Cirfel, foo, nonr BEJ_AC, GD_LBC, DF<br />

J_AC, cr BE sin a, EC z=: cos a, DG =: sinb, GC<br />

= cosb, DF = sin (a-f-b), FC = cos (a-j-b). Sro;<br />

gcg cnbnu GHJ_AC eg GI:^ AC, fon er DF = DI + IF<br />

;= DI-fGH. mil et<br />

GH<br />

— — sin a, eHer<br />

GC '<br />

GH = GC X sin a =: cos b X sin a.<br />

So ^DGK = R, fno er A DGI «>o DGK 00 FKC<br />

rsj EEC, oltfno DI : DG = EG : BG; falgdisen DI<br />

DG X EG<br />

z:= •—^^ , men BG = i, DG = sin b, EC<br />

BC<br />

:= cos a, oltfflO DI = sinb cos a; bo nu DF = GH<br />

/_DI, fno cr<br />

sin (a -|- b) ^3:: sin a eos b -j- cos a sin h<br />

Sigclebeg er<br />

FG =; cos(a-f-b) = HC — HF = HG —• GI


93Jen<br />

HC<br />

GC<br />

oltfao<br />

cos a<br />

HC = GC X cos a := cos b X cos o<br />

So ADGIeNjBEC, fno<br />

GI:DG = BE:BG, oltfoo<br />

39<br />

DG XBE<br />

GI =<br />

BC<br />

SRen DG := sinb, BE == sin a, BC =: i; oltfo*<br />

GI sin a X sin b<br />

golgdtgen, bo FC = HG —GI er<br />

cos (a -j- b) := cos a cos b — sin a sin b.<br />

§. 6. SJlaor ©inug og Cofinug of te SSinfler, a 03 b,<br />

ere givne, bo ot finbe ©inug 03 Cofinug til bcreg Sifferentg.<br />

Sob z_ ACB ^ a, BCD = b, bejTrtv meb fHabiai<br />

= I en Cirfd.<br />

gcelbcg nu DE_LAC, FGJ_AC, DFJ_BC; forteJfc<br />

8Cg enbvibere DE til T, broseg HFigtEC, FG JLAC, BK<br />

± EC, fnn er DE = sin (a — b) = EH — DH = FG<br />

— DH. 3 AGFC er<br />

GF<br />

—— =: sin a , oltfoo<br />

FG<br />

GF FG sin a = cos b sin a<br />

Cnbvibere er<br />

A DHF f-o THE evj TEG


40<br />

BC = If altfno HD =: sinb cos a, fjlsdtgen<br />

DE —^ sin (a — b) -— sin a cos b — sin a sin b<br />

EC = cos(a —b) = EG+GC = HF+GC;<br />

men \ AEGC ev<br />

:— cos a, Oltfoo<br />

FG<br />

GC FC cos a —~~' cos 1> cos a<br />

S5« AHFDCNJBKC, foo er<br />

BFjFD = BK:BC, oltfoo cc<br />

FD XBK<br />

HF =; — == sin b slu a , eller<br />

EG cos (a — b) cos a cos b -\- sin a sin b<br />

S U I. Se fimbne gormler lobe (Ig u&tri;ffc i eet i<br />

gorbinbelfe meb be §. 5 funbne fnnlebeg:<br />

I) sin (a 4^ b) --~^ sin a cos b 4^ cos a sin b<br />

II) cos (a 4^ b) cos a cos b ^ sin a sin b<br />

Stnnt, gormlcme sin (a —b) 03 cos(a —b) labe ffg 09=<br />

fao ublebe oeb i gormlerne for sin(a-[-b) 09 cos(a-|-b)<br />

fit fojttc b == — b. ^et inbfeeg jiu let, at, naar b<br />

iigger i f»rfte fioobrant, ia ligger .—b t fjetbe; men<br />

beng gunitioner ere eUcrg of famme rccHe ©t«rtelfe,<br />

fom b, oltfao er sin (— b) ==z — sin b, cctf (-.- b)<br />

5= 4-'=°s''' ''eraf fslgcr altfaa goranbringcn i Ze^ui<br />

\ gormlerne fpr sin (a — b) 09 cos (a — b).<br />

f. 7, ^oged<br />

?in (a -f- b) = sin a cos b -j- cos a sin b<br />

Sin (a -— b) -=: sin a cos b — cos a sin h<br />

eg nbbcrcg, ©umtrien btpibercg ttiei) 2, \a


IV) cos a sin b := i sin (a-j-b) — -J- sin (a — b)<br />

Cnbvibere ^ove«<br />

cos (a -j- b) •~-~ cos a cos b — sin a sin b<br />

cos (a — b) z:^: cos a cos b -j- sin a sin b<br />

Tlbbcrcg be og ©ummen bivibercS meb 2, foo cr<br />

41<br />

V) cos a cos b •=: 4^- cos (a -}- b) -f- -J- cos (a — b)<br />

©ubtro^ereg ben avetjte fro ben nebetfte, eg ber bivtbereS<br />

meb 2,<br />

VI) sin a sin b =r= -J- cos (a — b) — •§•


42<br />

Sivibereg i ScrHer og 9?«vner meb cos a cos b, er^olbeS<br />

sin a sin b<br />

^± T<br />

cos a cos a<br />

tS(a4:b) = . —<br />

sin a sin b<br />

1 4- -7<br />

cos a cos b<br />

gner<br />

ter a 4- tg b<br />

XI) tg(a + b) = ---^ T<br />

1 4-tgatgb<br />

©fftteg i benne germcl a ^= 45°, foo »c<br />

lE! 45° -j- te b<br />

jnen tg45° = i, oltfoo<br />

I +teb<br />

XII) ts(45° + b) = -^--^<br />

I —tgb<br />

Si3dcbe6<br />

xm).g(45''-b) = ^fj<br />

§.9. ©ffttcg a = b, foo er^olScS Sormlcrne for<br />

te bebbclte SSinfler, ellcr of I) felger<br />

XIV) sin 2 a =z= 2 sin a cos a<br />

of 11) fal3er<br />

XV) cos 2 a cos a' — sina*<br />

So sin a' = I —cos a', fnn, ^vii bette inbfofttcg iftebct<br />

for sin a', erf)olbeg<br />

cos 2 a =1: cos a' — 1 -j- cos a*<br />

= 2 cos a' — I<br />

StgelcbcS l^vig ber ftrtte?<br />

cos a' = I — sin a', ft<br />

«os2a = I —2sina»


43<br />

2(f biffe to (Ibfte gormler ubiebeg attcr, ^vi« sa f«tte« lige/<br />

fcor meb m,<br />

^vornf<br />

cos m 2 cos J- m' — i<br />

sin m z=: i ^ 2 sin j- m*<br />

XVI) sin^m<br />

XVII) cos^m<br />

___ » / I — cos ra<br />

= \fL±l<br />

3<br />

Snbffftteg t XI) osfna a = b, fno et<br />

XVIII) tg2a z=<br />

2 tg a<br />

§. 10. 2l'nvcnbeg nu be trt'gcnometrifTe gunctioner til<br />

^ttnnglcrg SBeregniiig, ba funne biffe vare enten t ct 'plon,<br />

fonlcbcg fcm be i 'pinnimctricn betrogtebe Sriongler, eller<br />

ogfnn, ^vig vi tffnfe og fro 'Joppunctet i et trefibet jjij^ne<br />

meb cn vtlfnnrlig Slabiug befPreven en ^uglc, vilbe be ^la;<br />

ncr, ber inbeflutte jjjernct, blive ©torcirfler, eg fonlcbcg vil<br />

en trcjibct gigur bnnncg pan .Suglcng Overflobe, inbefluttet<br />

nf Siuerne of be tre ©torcirfler, ^vilfet fvnrcr til bet tre;<br />

fibebe J^ijarne; benne gtgur fnlbcg et fp^trrifft Xrinn;<br />

gel, og onvenbeg 'Jrtgonometrien pnn biffe ^rinnglerg S&ei<br />

rcgning, ba fnlbcg ben fp^ceriff 2rigonometrie; ^vorimob<br />

?tigonometricn, onvenbt pnn be plone Sriongler, fnlbcg plon<br />

'itrtgonomctiic,<br />

%te ©ti;ffer tjcne olminbdigen til foovel at beftemme<br />

ft plant fom et fp^trrifFt ^rtonsd; bo3 er veb bet plane<br />

Srtangd tre SSinfler ingcn til(tr«ffdtg SBeftemmdfe, bo bifffe<br />

iffe ere of ^innnbcn unfl^fl'ngi3e, men flebfe tilfommen aR,


44<br />

Cr blonbt be opstvne ©ti;ffet tilli3e 6en 35eflemmclfe, «f<br />

ben ene givne SSinfd cr en ret, bo Ictteg 6eti;beli3cn SSereg;<br />

«tn3en; berfor vil blive of^nnblct f^rft 6e plone retvinfiebe,<br />

bernffft be plone ffjtfvvinflebe 2;rton3ler, 03 lt3elcbel of ben<br />

fp^OfrifTe 5ri3onometcie ferfl be retvinfiebe, bernfffl be (Tjav;<br />

»inflebe fp^fsrifTe 5rian3ler.<br />

§. II. 93ete3ne vt i et retvinflet plont 'Jriongcl fyy,<br />

pot^cnufen meb h, Cot^eterne meb a 03 b, be over for bem<br />

liggcnbe SSinfler meb ^ eg B, foo inbc^olber felgenbe 'Jabel<br />

fllle mulige 5ilf«lbe meb bereg Oplflgning:<br />

h, a<br />

a, b<br />

h, A<br />

a, A<br />

h<br />

A<br />

(I<br />

b<br />

B<br />

a, B h 1 h<br />

b \b<br />

b = V(7i-}-fl)(^i —«)<br />

sin^ = —<br />

h<br />

i B = T- '"• ^ = 90"<br />

h = Ya' + b'<br />

a = Ti sin A<br />

b = h cos A<br />

B = go° — A<br />

a<br />

siu A<br />

a<br />

tg A<br />

a<br />

cos B<br />

cigB


45<br />

2lf bell pvt^agorifTe ©«tning (I. §. 73) ubicbcg gorms<br />

Icvne h, a\b 03 a, b\}i; i ben ferfle er blot ©tercelfctt<br />

unber Slobtcgnet /i' — a- opleft i goctorcrne {h -j- «) 03<br />

(h — a), for ot gjere ben bcqveni til logoritljmifT 9Iegning.<br />

A tiQ B ubfi;lbe l^inonbcn ftebfe til 90"; er ben cue oltfoa<br />

given, bn ^nveg ogfnn ben onben. Se evrige gormler felge<br />

of gorflnringen pan be trigonometrifFe gunctioner §. 2.<br />

21 n m. ©om eiempler poa SSeregninggnmabcn roetc givct<br />

Selgenbe:<br />

I) Scengben af en lobret ©tift KL = 15 ^ob 7<br />

Stem. Seng ©Epgge foraavfagct af ©olen paa en l;Dri=<br />

jontal glabe ware LM = 21 Sob gJ !£om. eretgg=<br />

maal, ^»or (lot er 2:_KML ellcr ©oleng Jjeibe ooer<br />

.giorijonten? Sette cr Silfcelbct, a, b.<br />

a = 15/5833; b = 21,7917<br />

log a =: 1,19266<br />

log b z= 1,33829<br />

tg"^ = 9^85437 ^ = 35° 34'7"<br />

gller / KML, bet cr ©oleng ^eibe er 35° 34'7".<br />

SSilbe oi begfornben beregne KM = 7i, faa er<br />

log a ==1 1,19266 log 6 = 1,33829<br />

-(2 (2<br />

2,38532 3,676g8<br />

a' = 242,84<br />

i' = 474,88<br />

717,72<br />

log {a- 4- &') 2,85595<br />

2)-<br />

1,42798<br />

h = 26,791 = 26 Sob 9,'- itom.<br />

II) sgeb goben of et lobret ftaaenbe 2;ttatB cr maalt<br />

en I;ori}ontal Orunblinie, flor 534,7 Job, og fra beng<br />

Cnbcpunct bcflemt 55inElen til Saavtigefitnfen, flor aji^<br />

17'24", l;vor l)»it er b« Saaniet?.<br />

^it et given


46<br />

a = 534'7<br />

B = 2i"i7'34"<br />

log rt = 2,72811 Iog« = 2,72811<br />

log cos B 9'969^3ip I°S tg -B = 9/5907i<br />

2,75881 2,31881<br />

log h = 573'86 log 6 = 208,36<br />

Slltfaa Xaarnetg .^eibe 208,36 gob, 03 Sinien neb til @t«nb«<br />

pnnctet 573,86 gob.<br />

§. 12. jpoveg ct (Tjccvvinflet ?riangd, ^vig tre SSinfler<br />

betegneg meb A, B, C, ^vig ©iber BC, AG eg AB ui<br />

ville for ^ert^ebg ©fi;lb betegne meb a, b, c, fao, i)wi<br />

^ert brogeg ^erpenbicuteren AD, bdeg 'Jrtonglet i to ret;<br />

vinflebe 5riangler.<br />

3(f A ABD felger AD = AB sin B = c sin B, of<br />

A ADC felgec AD =: AC sin C = b sin C, oltfoo c sin 5<br />

— b sin C, eller osfoo<br />

C : b sin C *. sin B, b. e.<br />

©iberne for^olbe (13 fom ©inug of be over for bem ligsente<br />

SSinfler.<br />

3ff bet retvinfiebe ^riongel ABD felger<br />

AD C sin B<br />

BD = c cos 5<br />

•Jogeg AD of A ADC, foo er<br />

AD' = AC'—DC<br />

= &= —(a —BD)'<br />

CHcr<br />

(csinB)' = t' —(a —ccosiS)*<br />

3(ltfoo<br />

c'sinJB' = 6' —a*-}-2accosj5 —c'cosB'<br />

J^vorof<br />

C= (sin £'4-cos5') —2 ac cos JS-j-rt' = 6'


SOicn, bo slaB*-^-cosB^ = I, foo er:<br />

6' z= a' — 2 ac cos B-j-c'<br />

47<br />

5ngeg 'Proporttonen a: b =z sin A: sin J?, fno er<br />

rt-j-6ta = sin ^-j-sin B : sin ^<br />

og<br />

a', a — b =: sin A: sin A — sin B<br />

^lltfoo<br />

a-\-b: a — 6 = sin A-\-SinB : sin A — sin B<br />

9Ken<br />

smA-\-smB =^ 2s!n^ (^-j-i)cos 5 (y4—J5)<br />

sin A — sin B = 2 sin ^ (^ — B) cos !r (^ -j- B}<br />

(§. 7, VII og VIII)<br />

2lltfan<br />

a + b-.a — b = sm y (^A-^ B) cos \ {A — B)<br />

: sin I- {A — B) cos ; (iA -j- £)<br />

Sivibereg meb cosi(^ — B) cosl(A-{-B), fno er<br />

sin ^(A+B) sin .', (^ — B)<br />

a-\-b : a — 6 =: cos >- {A-]-B) ' cos t(iA—B}<br />

3:<br />

a^b:a-b = tgi (^-j-B) : tg i(^-B)<br />

(§. 2. 6, 7).<br />

§. 13. spoo be §. 12 bevifte tre 3(nnlogier flatter (tg<br />

S&cregningen of be plane fijcrvvinflebe ^rinnglcr.<br />

I) Scr vare given tre ©iber, ^crof ffol feges en SSinfel.<br />

Se ^oveg<br />

a' = 6' — 2 6c cos A-\- c<br />

3lltfaa , .<br />

' ^ 6' -f- c' — a'<br />

cos A =<br />

26c


48<br />

Scnne gormcl liber tmi&Icrtib of cn bobbelt ll6c


6-j-c-f-rt 6-j-


50<br />

eg bo et;<br />

tgUB-O == ^ tgK5 + C)<br />

B = ^(B + 0 + i(B-C)<br />

C=i(B-HO-KB-C)<br />

Sen (t^rre of ©iberne betegneg meb 6, ben minbre meb &,<br />

SSore 6 og c iffe umibbclbovt givne, men tgjennem Sogorit^;<br />

mcr, lettebeg SSercgningcn of<br />

6 —c<br />

.- vcb Ot f«tte<br />

64-c<br />

c<br />

T<br />

= tgM, bn er<br />

b — c<br />

6 -j- c<br />

I — tg M<br />

=<br />

I -j- tg M<br />

tg(45°-M)<br />

(§. 8, XII),<br />

bet ^cte Ubtr^f fr«ver foolebeg tfl jln 9&ercgntng blot trigo;<br />

nometrijFc 'iovlcr.<br />

^et ec given «, b. A, ^vorof '<br />

oltfoa<br />

« : 6 = sin A : sin B,<br />

b<br />

.sin B = •— sin A,


51<br />

Set er ^er olbdcg ubefkmt, om B (Tol togeg over cller<br />

unbcr 90°, meb minbre forub vib«g, ^vorlcbeg ^rinnglet ffnl<br />

vccre bejTnffent, cller og om rt> 6 (3»fr. I- §. 52),<br />

jjoveg B, bo er C = iS,o° — {A-\-B)<br />

og<br />

rt sin C a sin (,-_/ -j- j9)<br />

sin A sin A<br />

IV) Cen ©ibe, cn ^ogliggenbe og en overfor ftooenbe SSinfel.<br />

ijer ere givne a, A, B,<br />

C = 180° —(.A+ B)<br />

a sin B<br />

h = sin A<br />

a sin C a sin (A -j- B)<br />

sin A sin A<br />

V) SSore een ©ibe eg to ^oglig3enbe SSinfler, eller a, B,<br />

C, givne, bo fanbteg let<br />

A = i8o° —(B-j-C)<br />

^vorveb oltfao ^ilftrlbet brogteg til bet foregooenbe.<br />

3lUe 'itlfaflbe inbeflutteg oltfoo beqvemt t felgenbe 5obd:


52<br />

a, b, c<br />

a, b, C<br />

a, 6, A<br />

a,A,B<br />

a,B, C<br />

A<br />

IB<br />

c<br />

B<br />

C<br />

e<br />

a<br />

c<br />

C<br />

A<br />

6<br />

c<br />

r(s-5)(s-c)<br />

I'sfs — a)<br />

s = 4-(rt-j-6-j-c)<br />

tg4:(^-5) = ^4 *§i = B<br />

a sin C<br />

sin ^<br />

6 sin ^<br />

sin B ==<br />

C =<br />

rt<br />

i8o° —(^ + 5)<br />

rt sin C rt sin (^ -j- B)<br />

sin ^ sin A<br />

asinB<br />

sin A<br />

a sin fA 4- B)<br />

C = —-7<br />

Sin ^<br />

180'—(^4-B)<br />

A = i8o°—(B-f C)<br />

a sin B<br />

sin(B-f-C')<br />

a sin C<br />

'^ sin (£ -j- Q


21 nm. €ot n


54<br />

a = 53'5833<br />

b •=• 44,7083<br />

rt-j-6 = 98,2916<br />

rt —6 := 8,8750<br />

v^-j-JB = 126° 42'6'^<br />

^iA+B) = 63 21 3<br />

log(a —6) = 0,94817<br />

Clog(rt-f-6) = 8,00748<br />

tg 4 (A-fB') = 0,29944<br />

ts\(.A — B) = 9*25509<br />

i-iA—B) = io°n'59"<br />

i i^+B) = 63 21 3<br />

A = 73° 33' 2"<br />

.S = 53 9 4<br />

9?(»re iftcbetfot rt 03 6 bereg gogarit^mcr givne, ncmlig:<br />

logrt = 1,72903<br />

log 6 = 1,65038<br />

6<br />

tgM = log— = 9,92135<br />

M 39° 50' 24'*<br />

45° —M = 5 9 36<br />

tg(45° —M) = 8,95571<br />

tg i(_A-{-B) = 0,29944<br />

9'255i5<br />

i(^ —B) = 10° 12' 4"<br />

HA + B) =: 63 21 3<br />

•^ = 73° 33' 7"<br />

B = 53 8 59<br />

gorfljellen of 5" Ijibr^rer ft« gcilcn \ b?n fjbfte ®e;<br />

(intal i SogarttOmernc,<br />

^Jcu fin,bcg let c<br />

log rt == 1,72903<br />

Csin^ = 0,01815<br />

sin C = 9,90404<br />

logc = 1,65122<br />

c = 44'794 == 44 If- 19 2:0m.


III)<br />

£a er<br />

a = 60735<br />

6 = 78468<br />

^ ^ 33° 45'37"<br />

log 6 = 4,89469<br />

C log rt = 5,21656<br />

sin A = 9,74486<br />

9,85611<br />

B — \ 45° 53'15"<br />

1134 6 45<br />

Sageg ben ferfle ssoerbie, ba et<br />

C z= 100' 21'<br />

^craf<br />

log rt = 4,78344<br />

Csin^ =: 0,25514<br />

sin C = 9,99288<br />

logc = 5,03146<br />

c = I 07512<br />

fCagcg ben anben SSurbie fer B, ia er<br />

C = 12° 7'38"<br />

oltfoo<br />

log a =<br />

C sin yl<br />

sin C =^<br />

4,78344<br />

0,25514<br />

9/32239<br />

55<br />

4-36097<br />

c := 22960<br />

®ct er albcleg ubeflcmt, f)vUUn sBwrbie vi ^ove at<br />

tage, meb minbre 6 •< a ellcr bet paa anben SJlaabe ct<br />

bcftcmt, om B er flump eller fpibg.<br />

§. 15. ©fol glnbe;3nb^olbet trigonometrifft beflem;<br />

meg, fnn ^vig vl onfee a for ©runblinte og falbe fro ^op?<br />

punctet A en "perpenbicultrr, foo er benne, ber et ijeibcn<br />

i 'Jrinnglct, liig<br />

b sin C


56<br />

oltfno globcinbl^olbet Z<br />

4" c^b sin C<br />

Sre nu onbre Sele enb biffe beftemtc, bo finbeg biffe<br />

let berof veb be for^en givne gormler. g. Sy. ere tre ©i<<br />

ber givne, bo ec<br />

.„ r Vs(s-rt)(s-6)(s-:;)<br />

sin O ^:zr „ .—<br />

4-rt6<br />

altfflfl 3nb^olbet<br />

Z = Ys (s — rt) (s — 6) (s — c)<br />

(3»>fc. I. §. 147).<br />

^pj)ctti\f Si'lgonomcfrie.<br />

§. 16. S^ctcgneg ©iberne t et fp^OfrifFt 3;riongel meb<br />

a, b, c, SStnflerne, ber ligge beroverfor, meb A, B, C,<br />

foo, ^vtg fro ben tilfvorenbe Sugleg Centrum O, brogeg 3va;<br />

bicrne OA, OB eg OC, og t ^pionet AOB brogeg Songem<br />

ten AD, inbtil ben (TjOfrer COB'g "pion t D, eg ligelebeg i<br />

planet AOC '^ongenten AE, fnn, nnor tillige DE brogeg,<br />

cr nf A ODE<br />

DE' = OD' -f- OE' — 2 OD X OE X cos DOE<br />

(§. 12).<br />

Sigclebeg er nf A ADE<br />

DE' = AD' + AE' —2AD X AE X cos DAE<br />

Qlltfno<br />

OD= -j- OE' — 2OD X OE X cos DOE<br />

= AD=-j-AE' —2AD X AE X cos DAE<br />

©fftteg AD^ eg AE' ever poo ben mebfotte ©tbe mc6 mob*<br />

fot 'Jegn, fon er<br />

00'^ AD' = OA', OE' —AE' =;= OA'^<br />

olffaa


57<br />

20A' —20D X OE X cos DOE = —2AD X AE<br />

X cos DAE; men DOE =: rt, DAE = A, felgeltgen,<br />

^vig ber bivibereg meb 2OA', cr<br />

OD OE AD AE<br />

I X —^ X cos rt = X — X cos .4<br />

OA OA OA ^ OA<br />

!Oiew<br />

OD —~ sec AOD = sec c<br />

OA<br />

3(ltfao<br />

OE -<br />

- -— sec AOE = sec 0<br />

OA<br />

AD<br />

= tg AOD = tg c<br />

OA<br />

AE<br />

° ^<br />

^- = tgAOE== tg&<br />

I — sec c sec 6 cos a ^r: — tg c tg 5 cos A<br />

!9iultiplicereg ollevegne meb cose cos6, foo, bo of en^vet<br />

SSinfel ©econtcn multipliceret meb Sofinus er ligcftor meb i,<br />

5nngentcn meb Sofinug ligcftor meb ©inug, foo cr:<br />

.^vorof<br />

cos c cos b — COS a '^zz — sin c sin 6 cos A<br />

COS a := COS 6 cos c -|- sin 6 sin c cos A<br />

:jlltfno funne famtligen ubvifleg<br />

A. l) cos a cos 6 cos c -j- sin 6 sin c cos A<br />

2) cos 6 ^^ cos rt cos c -j- sin rt sin c cos B<br />

3) cos c =^ cos rt cos 6 -j- sin rt sin 6 cos C<br />

§. 17. 5lf ben §. 16 beviifte 2fnnlogte mellem 3 ©i<<br />

ber og en SSinfel Inbe be ^vtige fig nu onoli;ti|! ubvifle,<br />

•Jogcg Signingcrne A. i) og A. 2):


58<br />

cos a —~ cos 6 cos c -j- sin 6 sin c cos A<br />

cos 6 —'— cos a cos c -j- sin a sin c cos B,<br />

eg multiplicercg of biffe ben ftbftc meb cos c og obbereg til<br />

ben ferfte, foo cr^olbeg felgenbe:<br />

eos rt (i — cos c') =: sin b sin c cos A<br />

-j- sin a sin c cos B cos C<br />

So I — cose' = sine', foo, ^vig everolt bivibcre*<br />

meb sin c, er^olbeg<br />

cos rt sin e sin 6 cos ^ -j- sin a cos C cos B (I)<br />

Sigclebeg fon er^olbeg<br />

cos c sin rt sin 6 cos C-j- sin c cos rt cos B (II)<br />

SOiUltiplicercg II meb cosB og obbereg til I, fno er<br />

eller<br />

cos a sin c (i — cos B'^ sin 6 cos y/<br />

-j- sin 6 cos C cos Br<br />

cos rt sin c sin B' ~~~ sin 6 cos ^ -j- sin 6 cos C cos j5 (III)<br />

Sigclebeg<br />

cos rt sin 6 sin C —"" sin c cos ^ -j- sin c cos B cos C (IV)<br />

^Diultipltccreg III meb sin c, IV meb sin 6, foo fommer Sige;<br />

(lort begge ©teber pon ^eire ©ibe of Sig^ebg;5egnet; felgdigcn<br />

cos rt sin c' sin £' ^= cos rt sin 6' sin C<br />

j^vorof<br />

sin c sin j5 =^ sin 6 sin C<br />

©oolebeg fV'embeleg;<br />

B. i) sin a sin B sin ^ sin 6<br />

2) sin rt sin C sin y^ sin c<br />

3) sin 6 sin C = sin 5 sin c.<br />

3nbfatteg i I<br />

sin B sin rt<br />

" sin, A


foo e»<br />

59<br />

sjn B sin rt j , . T,<br />

eos rt sin c = — cos A -J- sin a cos c cos B<br />

sin ,•/<br />

Sivibereg meb sin « eg erinbreg, ot Cofinug, blvlbe*<br />

vet meb ©inug, er ligcftor meb Sotongenten, bo er^elbeg<br />

cot rt sin e sin jS cot A -j- cos C cos B<br />

2tltfoo er iolt<br />

C. i) cot rt sin c sinB coty/-j-cos r cos B<br />

2) cot a sin b sin C cot ^ -j- cos 6 cos C<br />

3) cot 6 sin c :^=: sin ^ cot B -j- eos c cos A.<br />

3nbfffttcg i I<br />

sin C sin B . sin A sin &<br />

Sin c := , -=— sin a := ^;—,<br />

sin B sin B<br />

foo er<br />

COS rt sin C sin 6 sin ^ sin 6 Cos c cos B<br />

:—5, = Sin b coaA-i :„<br />

sin Ji sin B<br />

sin 6<br />

bivibereg meb —=, bo er<br />

sm iJ<br />

cos rt sin C = sin B cos ^ -j- sin A cos c cos B (V)<br />

Sigclebeg<br />

cos c sin ^ z= sin B cos C -j- sin C cos rt cos B (VI)<br />

SJiuItiplicereg VI meb cosB 03 obbereg til V, foo er<br />

cos a sin C(i — cos BO<br />

sin B cos ^ -j- sin B cos C cos B.<br />

©o:tteg I — cos B' = sin B", 03 bivibereg meb sin B,.<br />

foo er<br />

cos rt sin C sin B = cos ^ -|- cos C cos B,,<br />

oltfao<br />

cos A 5== —•- cos B cos C'-f- sin B sin C"cos ct


6o<br />

^ilfnmmctt cr oltfno:<br />

D. i) cos^= —cosBcos C-f-sI°BsinC'cosa<br />

2) cos B —cos ^cos C-j-sin ^sin Ccos 6<br />

3) cos C =^= — cos A cos B -j- sin ^ sin B cos c.<br />

§. 18. SScb Jjjfflp of biffe §. 16 03 17 ubviflcbe 3fna(<br />

logier. A, B, C, D, lobe fig nu olle 2tlf«lbe for be fp^ti;<br />

f?e ^rionglcr bercgne. ©impleft ere be, ^vort een of SSinf;<br />

lerne er 90", 03 begforuben to onbre ©ti)ffcr givne. ©aale;<br />

beg opftoner be retvinfiebe fpf;


cot c sin rt sin B cot C-|- cos rt cos B<br />

men, bo C = 90°, er cot C = o,<br />

felgcltgen<br />

oltfoo<br />

II) rt, 6.<br />

©00 er<br />

2ff C. 2)<br />

cot 7i siu rt = cos rt cos B<br />

cot h sin rt<br />

cos B = = cot A tg a<br />

cos rt<br />

tg^<br />

cos h cos rt cos 6<br />

cot rt sin 6 sin 90° cot ^ -j- cos 6 cos 90°<br />

bo sin 90° := I; cos 90° = o, fao er<br />

ellcr<br />

III) A, ^.<br />

©00 er<br />

cot rt sin 6 =r cot A<br />

t$A = -r-T<br />

sra o<br />

sin rt sin h sin .


62<br />

©0geg B, foo er D 3)<br />

oltfoo<br />

eUcr<br />

cos C —~ — cos A COS B ~\-sin A sin B cos c<br />

IV) a, A.<br />

S^ex er<br />

^tltfoo<br />

cos A cos B ~~~ sin ^ sin B cos h<br />

cot B tg A cos A^<br />

sin ct<br />

sin n = -: ^<br />

sm^<br />

enbvibere of C 2) fooeg<br />

3(f D I) felger<br />

cot rt sin 6 = col A<br />

, y coty^ tgrt<br />

cot a tg A<br />

cos A = — COS B COS C-j- sin B sin C cos a<br />

oltfoo, bo C = 90°,<br />

COS A = sin A cos rt,<br />

er<br />

. _, cos ^<br />

sin B ——•<br />

V) rt, B.<br />

.^er er<br />

tg h = -—cos<br />

.0<br />

cos a<br />

tg 6 = sin rt tg B<br />

cos ^ =: cos rt sin B<br />

^vilfet ublebcg of be foregooenbe ^ilf


ijer er<br />

7 tot B T^ 4<br />

SOS h / := cot B cot A<br />

CHS A<br />

SOS n T = —<br />

siu B<br />

63<br />

Sn be trigonometrifTe gunctioner ftebfe ^ere til to for*<br />

(Tjellige SSinfler, fnn cr bet ubeflcmt, l)vilfen nf biffe ffol tn<<br />

gcg; fom ofteft er ben 55eftemmclfe gjort, at ingcn of ©t/<br />

bcrnc eller SSinflerne t et fp^trrifft ^rinngcl bar overfTribe<br />

i8o°; bn fan iffuu 5vivl opftonc, l)Vor vt ^nve ben fegte<br />

©terrelfe bcftcmt igjennem en ©inug, bo benne fvorer ftebfe<br />

til to SSinfler, ber ubfwlbe f)inanbcn til i8o°.<br />

3miblertib vibe vi flebfe, nt tgrt = sln6tg^,- bo<br />

nu unbcr ben gjortc 3lntngelfe 6 < i8o°, er sin 6 pofitiv,<br />

nitfnn faner tgrt fnmme 'Jegn fom tg^, eller Sot^eten eg<br />

ben ovecforliggenbc ©tbe ere enten begge minbre eller ftarre<br />

enb 90°, faalebeg bliver bet enefle tvtvlfomme 'Jilffflbe «, A.<br />

SSi funne altfno inbbefotte oHe 'Jilftrlbe i felgenbe %abe\:


64<br />

I) h, a<br />

II) a, b<br />

III) h, A<br />

IV) a, A<br />

V) rt, B<br />

VI) ^, B<br />

cos 6 ^1=<br />

sln^ =<br />

cos B =<br />

COS A =^<br />

tg^ =<br />

sin


65<br />

cos h = 9,45861 sin rt = 9/51747 'y « = 9/54238<br />

cos (t = 9,g7509 siu ]i = 9,98127 tg h = 0,52266<br />

cos 6 = 9,48352 slu^i = 9,53620 cosB = 9,01973<br />

6= 72° 16'29" ^=20° 6'12" B= 83° 59'36"<br />

,-/ maa I;cr ta%ii < 90°, bo « < 90".<br />

2) rt = 132° 15'23"<br />

6 = 57 19 28<br />

cos rt — 9,82766 n tg rt = 0,04165 n tg 6 = 0,19288<br />

cos 6 = 9,73230 sin b = 9,92518 sin a = 9,86931<br />

cos h = 9,5599611 tgA= 0,11643n tgB = 0,32357<br />

7t=iii°i7'i5" ^=127" 24'37" B= 64° 36'20"<br />

3) rt = 16° 33' 29"<br />

^ = 23 27 56<br />

sin rt = 9,45482 tg rt =: 9,47322 cos^ = 9,96251<br />

sin^= 9,60010 tg^ = 9,63759 cos rt = 9,98161<br />

sin/i = 9,85472 sin 6 = 9,83563 sin B = 9,98090<br />

ft^i 45°4i'55" ^,^1 43°i3'42" ^ ^ j 73° 8'o"<br />

(134 18 5 (136 46 18 (10642 o<br />

^er er bet albcleg ubeflcmt, I;t)ilfen fSccrbie ber f!af<br />

ta^eo; imiblertib tageg ben fwfte 25arbie af 6, faa foa=<br />

ter bertil ben ferfle af 7t, ba rt < 90", 09 cos h<br />

cos a cos 6; felgcligen sprobuctet i bet Silfojlbc<br />

pofitiot; altfaa /i


66<br />

cos A = 9,4536636<br />

sin B = 9,962177:^<br />

cos rt = 9,4914863<br />

rt = 71° 56'7" 47<br />

cos B = 9,6018619<br />

sin A =9,9817087<br />

cos b = 9,6201532<br />

6 = 65° 21'13''09<br />

NB. J?er ftnaer alleoegne for ^ortljebg ©Eplb be trigono;<br />

metrifPc gunctioner iftebct for bereg 2ogaritt)mer, f. Cr.<br />

sin a for log sin a. Sigt'Icbeg bettjbcr n feiet bag til £0=<br />

garitljmcn, at ben frarer til en negatio etorrclfc.<br />

§. 19. Jjvtg ccn nf ©iberne t bet fp^crrifTe ^rtnngd<br />

vnr 90°, ba lobe lignenbe 2lffortninger, fom veb be retvinf;<br />

lebe fp^trriffe ^rtongler, fig forctnge, og fnnlebeg ligelebeg<br />

let nf to ©ti;ffer foruben benne givne ©ibe, ber v.ir 90°,<br />

be ^vrtge Sele fig beregne.<br />

§. 20. SScb be fFjttvvinflebe 'Srtnnglerg Seregntng,<br />

^vig vi vilbe onvcnbe 8ognritf)mer, vilbe, formcbclft be veb<br />

2(nologierne A, C, D forefommenbe 3(bbitioner og ©ubtrac;<br />

tioner, cn Ubeqvcm^eb opftnae, fom ttlbeelg nf^jcrlpcg paa<br />

felgenbe 9]tnnbe.<br />

jpnvbeg et Ubtri;f nf bm goritt<br />

X = rt sin IM -j- 6 cos M<br />

til ^vig SBeregntng ffulbe nnvcnbeg Sognrit^mer, fnn funbe<br />

vi ftebfe nntnge, ^vnb enb rt og 6 vnr,<br />

rt = 1- cos X<br />

6 = r sin X<br />

^vor r er cn cnbnu ubcfjcnbt ©tovrclfe, og X li^,flo^cg cn<br />

ubcfjenbt SSinfel, men begge bog givne vcb be to ovcuitnncnbc<br />

3@


altf'nn X bcftcmt, og ^ernf ntter<br />

rt 6<br />

cos X sin X<br />

3nbffftteg nu SSarbierne for « oj 6, fnn ec:<br />

x 1- cos X sin M -j- r sin X cos M<br />

= rsin(M-(-X)<br />

6?<br />

et Ubtri;f, ^vori X, funben igjennem tgX, og r, veb fin<br />

S(?qvntion, inbf«ttcg; bet Jjele Inbcr fig nu beregne veb So;<br />

gnrit^mer. 9icgningen fereg nu bcqvemmeft fnnlebeg. jjvig<br />

f. (£v. M = 63° 17'<br />

logrt = 9,87036; log 6 = 9,73097n<br />

3?u fTriveg log 6 og log «, fno nt berimellem bliver een<br />

Sinie. Siffcrentfen er log ty X; X togeg i 7llminbclig^cb faa«<br />

lebeg, ot r ftebfe bliver pofitiv; altfnn, ^vig 6 er pofitiv, i<br />

ferfte ijnivcivfd, er 6 negntiv, i nnben; imellem logrt og<br />

log 6 ffrivcg enten log sin X cller log cos X, eftevfom ^vilfcn<br />

of bem er fterft, bn ben ffnrpeft og lettefl Inbcr fig intcrpo;<br />

lere, og nu bercgneg ^ernf r veb at trtrffe benne mdlcmfntte<br />

ftebfe frn ben fterfte of Sognrit^merne logrt og log 6; bet<br />

evrtgc finbeg nu let. 3fltfnn:<br />

log 6 = 9,7309711<br />

log cos X = 9,88434<br />

log rt = 9,80736<br />

logtgX = 9,92361 n<br />

X == 320° o'48"<br />

M = 63 17 o<br />

X-j-M = 23° 17'48'<br />

r == 9,92302<br />

log sin (M-j-X) = 9'597i4<br />

logx = 9,52016


^8<br />

2t tt m. 3If ©itimucn X -f- M er bortfaftet 360".<br />

en Itanenbe goranbring l;aobe funnet fleet veb «<br />

(Rtte a = r sin X, b =: r cos X, og bo tr«£Ee fant:<br />

men til r cos (M — X).<br />

§. 21. 2(nvenbeg nu bcelg bet §. so fremfntte >Prini<br />

eip, bcelg onbre gorfortninger veb be jTjffvvtnflebe fp^arifle<br />

5rionglerg, bo lobe ligelebeg nlle 2ilf


fao c<<br />

69<br />

S sin ; (rt -j- 6 -f- 0 sin ', (6 -j- C — rt)<br />

2cos 4 A^ = ^ .^~^ .<br />

3(ltfflO<br />

jjvorof<br />

sin b sm r<br />

sin 6 sin c v<br />

betegneg ^er 4(rt-j-6-j-o) meb s, fao er:<br />

sin 4- ^ = %/"="•" («-fe)^;"0-g<br />

sin 6 sin C<br />

cos •<br />

4-^-= V -<br />

V /sin sin s sin (s — rt)<br />

siu 6 sin c<br />

. 2 Y sin s sin (s — a) sin (s — 6) sin (s — c)<br />

sin A 3= . , .<br />

sm 6 sin C<br />

t , .£ __ y^sln (s — 6) sin (s — c)<br />

siu s sin (s — o)<br />

2lf ^vilfe gormler cfter Omftffnbig^eber ben nnvcnbeg,<br />

fottt fParpeft beftemmer SSinflcn; ncmlig ben ferfte, noor<br />

SSinflcn er unber 90°, ben onben, noor ben er over, gorm;<br />

len for tg4;^ er flebfe n^eie, men nogct vibtljeftigerc enb<br />

be onbre.<br />

II) rt, 6, C.<br />

SSi ^nve<br />

f'na ^ovcg<br />

cos c : = cos rt cos 6 -j- sin rt sin 6 cos G<br />

©ffttcg ^er<br />

cos rt r cos IM<br />

sin a cos C = r sin M


3(ltfno<br />

70<br />

sin rt cos C<br />

te M = : z= tg a cos C<br />

cos rt<br />

cos a sin rt cos C<br />

cos -M sin M<br />

cos rt<br />

cos f : ^ — cos (b — M")<br />

cos M ^ ^<br />

gor Ot finbe yj, fjnvcg ifelge C. 2)<br />

cot rt sin 6 : = sin C cot ^V -|- cos 6 cos C<br />

cot rt sin 6 — cos b cos C<br />

cot A = .——<br />

sin C<br />

gor ot bruge ben for^en funbne Jjjttipe* SSinfel, Inbcr<br />

eg multiplicere meb sin rt i Strllcr og 31«vncr, fan cr, ba<br />

cot rt sin rt = cos rt<br />

foo cr<br />

CJCer<br />

col A =<br />

cos rt sin 6 — cos 6 sin a cos C<br />

sin rt sin C<br />

©ffttcg ^cri M eg r, erbolbeg:<br />

cot^ =<br />

r cos M sin 6 — r cos 6 sin M<br />

r sin (6 — M)<br />

sin rt sin C<br />

sin rt sin C<br />

SSfffgeg ben (ibfte SSffrbie for r, ncmlig<br />

sin rt cos C<br />

sin M<br />

sin rt cos C sin (6 — M)<br />

sin M sin a sin C<br />

sin (6 — M)<br />

sin M tg C


sin M tg C<br />

tg^ =<br />

sin (6 — M)<br />

71<br />

ipno fnmme 'DJJnnbe vor B blevcn bcftcott, l;oig ben<br />

fywbe vffret ben omfpurgtc.<br />

Ill) rt, 6, A.<br />

Sjev f;nvcg<br />

sin 6 sin A<br />

sinB = — . tfelgc B. l).<br />

Sin rt<br />

©fnl C fegeg, fnn er:<br />

cot a sin 6 z:=: sin C cot A -j- Cos 6 cos C<br />

firttog ^er cot^ — rcosM<br />

cos 6 r sin M<br />

3tltfno<br />

Jlltfno<br />

cos 6<br />

cot rt sin 6 -— r sin (C -j- M)<br />

cos 6<br />

= -T-rjsin(C-hM)<br />

sm M<br />

sin M<br />

siH (C-j- Rl) cot rt sin b<br />

.^crnf fan nu C finbeg.<br />

©egcg c, fan er:<br />

cos 0<br />

sin M cot rt tg 6<br />

sin !\I tir 6<br />

tg rt<br />

cos rt cos 6 cos c -j- sin 6 sin c ctfs -/<br />

fffttcg ^er cos 6 r COS M<br />

sin 6 cos yf r sin .M<br />

(C. 2).


72<br />

foo r)ove«<br />

tg M = tg 6 COS A<br />

cos 6<br />

COS rt == cos (c — ]VR<br />

cos M ^ ^<br />

cos rt cos M<br />

^Vorof COS (e — ISI) = —<br />

cos 0<br />

IV) rt, B, C.<br />

©«gcg ^, foo cr<br />

cos A = — cos B cos C-\- sin B sin C cos rt<br />

fffttcg ^er<br />

3(ltfa(»<br />

cps B r cos JM<br />

sin B cos rt := r sin M<br />

tg M = tg B cos a<br />

cos B _,<br />

cos^ = cos(C4-M)<br />

cosM<br />

©0geg 6, foo cr, ^vig i G. 2) rt eitibijtteg meb b,<br />

cot 6 sin a sin C cot B -j^ cos a cos C<br />

flltfOO<br />

sin C cot B -j- cos fl cos C<br />

cot 6 = : •<br />

sm rt<br />

sin C cos B -j- cos rt cos C sin B<br />

sin rt sin B<br />

3nbffftteg ^crt r eg M, foo cr<br />

cot 6<br />

rsin(C-j-M)<br />

sin a sin B<br />

sin B cos rt<br />

tfien r =<br />

sin M<br />

flltfOfl


nitfnn<br />

eoer<br />

sin (C-j->n<br />

cot b = —.- ,;<br />

sin M tg rt<br />

sin M tg a<br />

'°^ ^^ sla(C^M)<br />

V) a. A, B.<br />

bo et<br />

tJtltfno<br />

©ffttcl<br />

.Jjcr er<br />

©egeg c, fan cr<br />

sin a sin B<br />

sin yl<br />

cot a sin (• sin B cot ^ -j- cos c cos B<br />

sin B cot yl —— cot a sill c — cos c cos B<br />

©ffttcg<br />

cot rt r cos M<br />

cos B r sin M<br />

cos B<br />

ts >I •—• COS B tg rt<br />

cot rt<br />

COS B<br />

sin B cot A = -.—- sin (c — M)<br />

sin M<br />

sin M<br />

?iq (c — M) =T= -—= sin B cot ^<br />

cos x><br />

©ijgcs C, fnn er<br />

sin M tg B<br />

tg^<br />

CCS A —— .— cos B cos C-j- sir* B siu Ccos rt<br />

COS B •*— r cos M<br />

sin B cos rt r sin M<br />

73


74<br />

©na er<br />

2fltfna<br />

tg M tg B cos a<br />

B<br />

cos A=^ yl<br />

~- cos (C-f- M)<br />

cos<br />

cos M -- I /<br />

_, , cos M<br />

cos (C-{- M) = cos A<br />

cos B<br />

V) A, B, C.<br />

©egeg rt, fnn cr<br />

cos^ i^ —• cos B cos C-^ sin B sia C cos a<br />

"Nltfan<br />

cos A -j- cos B cos C<br />

cos rt ^<br />

sin B sin C<br />

?OJcn, vcb nt trffffc frn i, ^oveg<br />

cos B cos C — sin B sin C -j- cos A<br />

1 — cos rt = r-^ . ^,<br />

sin x> sm C<br />

cos (B -j- O + cos ./<br />

sin B sin C<br />

eacr<br />

2 cos 4-(B 4-C-f-^ cos J-(B 4-C—^)<br />

2 sin ', rt" -:<br />

sm B sin C<br />

. , . f cos 4 (^-1- 7i -(- o cos,',- (B -j- C—.4)<br />

sai ] (I =1 Y ; -: 1<br />

sin B sin C<br />

f'na cr<br />

. / cos S cos (S — A)<br />

Sin 4 ci — y 1<br />

sin B sin C<br />

Jjnvbc vi tngct


75<br />

COS yl-\-cos B cos C-f- si" J5 sin C<br />

1 -j- cos rt : =<br />

sin B sin ('<br />

So var<br />

2 COS 4^ rt"<br />

3ntfnn<br />

cos . /-f- cos (/) — C)<br />

sin B sin C<br />

2 COS K •/ + -S — C) COS,; (7 —B-f Cj<br />

,.^Sfl<br />

ipvornf ba ntter fan ubicbcg<br />

sin B sin C<br />

cos S — B) cos (S — O<br />

sin B sin C<br />

cos S COS (S y4)<br />

tg4a= V —<br />

cos (S — B) COS (S — C)<br />

en 'Jnbel, fom inbe^olbcr nlle "Silffflbc, blcv felgenbe:<br />

rt, 6, c<br />

rt, 6. C<br />

A<br />

c<br />

yl<br />

( sin (s — 6) sin (s — c)<br />

sin 4 A = A ^-y—- "<br />

N sin b sin c<br />

. 1 sin s sin (s — rt,)<br />

N sin b sin c<br />

1 sin (s — 5) sin fs — c)<br />

•g M = J — . -'-•'•-J — —<br />

^ Sill s sm (s — aj<br />

s = 4(„-f-6-j-..)<br />

tg -il Z= tg rt COS C<br />

cos rt<br />

cos c COS (b — M)<br />

cos M<br />

tg IM := tg rt COS C<br />

sin (6 — M)


76<br />

#, 6, A<br />

«, B,<br />

a, A, B<br />

J.B,<br />

—<br />

C<br />

C<br />

B<br />

C<br />

c<br />

y/<br />

6<br />

6<br />

e<br />

C<br />

a<br />

sin 6 sin A<br />

sin B = '<br />

sin a<br />

tg M •=: cos b t^ A<br />

sin AI tg 6<br />

siu(C-j-5I) = — - 2 -<br />

tgrt<br />

tg M tg 6 cos A<br />

cos rt cos M<br />

cos b<br />

tg M =1= tg B cos rt<br />

cos B<br />

cos^ = : cos (C-j-M)<br />

cos M<br />

tg M = tg B cos rt<br />

sin M tg a<br />

*^^ sin(C-j-M)<br />

sin B sin rt<br />

sin^<br />

tg M == cos B tg rt,<br />

siu M tg B<br />

sin (c — M) = —-—,—<br />

tg.'i<br />

tg M ::= tg B cos a<br />

cos M<br />

cos XJ<br />

S^=i{A + B + C)<br />

( cos S cos (S ^)<br />

tm 4 u —.— J • T> • n<br />

N sin ij sm C<br />

f cos (S — B) cos (S — Q<br />

cos 4- c* —^ \i • • T> • ri<br />

N sm B sm C<br />

[ cos S cos (S — ^<br />

•g 2 « >| cos(S-B)cos(S-()


77<br />

gevfnavitJt fom bet ©i)gte beftemmcg gjentiem 'int!,o,cn;<br />

ter cUcr Sofinuffcr, ictn ingcn 'Svivl opjtnsf, i ^vtlfcu Civai<br />

bront btt fTal tngcg, nnnr vt nntnge nt ©iber og a^iuflcr<br />

(Tulle vffre miubce enb i8o"; ligelebeg nfgive gormlernc for<br />

be f)nlve SJtnfler ftffre $5cftcinmdfcr. J?vor iffe felve 23inf;<br />

len, men gorffjdlen mdlcm ben og jjjfflpcSSinflen, finbeg,<br />

bo bliver benne ftunboin negntiv; nnnr ben nitfnn givcg gjcu;<br />

ncm cn Scfinug, cr bet ntter tvivlfomt, enten gotfpjdicn fTal<br />

Vffre negntiv ellcr pofitiv J: enten bet ©egte er minbre clicr<br />

fterr* cub J?jfflpcviuflen. 3 f[«i'« "Silffflbc vil SSnlget nicl;<br />

Icm Opl,e»ningcrnc letteg veb folgeubc bet fpl)cfifTe ^rinngcU<br />

6"gcn|Tn6cr:<br />

i) ©ummen of to ©iber er ftcbf'e ftevre enb ben tre<<br />

bie (3^fr. ©tcvcotn. §. 26).<br />

2) ^'llc tre ©iber ere tilfnmmcn minbre enb 360"<br />

(©teveom. §. 27).<br />

3) Zo SSinfler tilfnmmcn cr flebfe minbre enb ben tw;<br />

Me -j- 180°.<br />

Svnnc ©fftning bcvifeg fnnlebeg nnnli;ttfrt.<br />

cos yl = — COS B cos C -j- sin B sin C cos a<br />

Stltfnn, bn cos (A-\- 180^) = —cos A, fnn er<br />

cos (^-|-180') = : cos B cos C—sinB sin Ccos «<br />

oltfno<br />

cos (B -j- C) = : cos B cos C — sin B sin C<br />

6os(B-j-0 —cos(^-|-l8o°) = — sinB sin C(l —COS rt)<br />

So siuB, sin C, I — cosrt ftebfe cre pofitive, foo er<br />

COS (A-{- ISO"-) > cos (B-j-O; men A-{-180' ligger imd;<br />

Icm 180° og 360°. 3meaem biffe ©tffubfer tiltagct ecjinug<br />

(tebfe fro — i til -j- i, bo tiUige B + C< 360°, men neb;<br />

venbigvtig B -j- C< .i^+180°.


78<br />

4) ©ummen nf oHe SSinfler er ftorre enb i8o°, miiv<br />

bre enb 540°.<br />

SSi ^nve<br />

cos 4- (^-|- B -I- C) cos \(B-{-C — y4)<br />

sin 4rt= == — • ~r3 • (^<br />

sin ti sin C<br />

jjer maae nebvenbigcn cos \ (^-j-B-j-O vffre negatto;<br />

tl)i sinB og sin C cic pofitivc B-\-C — yl


4 B = 66° 14' 30"<br />

B := 132 29 O<br />

ascrcsncg C af gcrinlen for tg ! (', f'" cr<br />

tin (s — rt) = 9,76660<br />

sin (s — 6) := 8,/'8M79<br />

C sin s =i:r 0,02683<br />

C sin (s — c) = 0,29091<br />

2)S,SNi3<br />

ly ' C z= 9,43706,5<br />

4C = 15° 17'59"<br />

C = 30 35 58<br />

II) a = 107° 19'34" 35<br />

6 = 86 27 28, 87<br />

(' = 112 19 13, 68<br />

Sa er<br />

tg rt = 0,50589111<br />

cos C =: 9,5795397"<br />

tg -M = 0,0854308<br />

M == 50° 35' r?" 77<br />

b = 86 27 28, 87<br />

6 —M z= 35 51 31, JO<br />

cos rt zzzz 9,47394inn<br />

C cos :M 1^= 0,1974049<br />

cos (6 — M) = 9,9087341<br />

cose =: 9,5800806n<br />

c = 112° 20'59" 23<br />

siu M = 9,8880259<br />

tgC = 0,386636811<br />

C siu (6 — M) 0,2322599<br />

tgA = 0,506922'in<br />

A = 107° 17'15" 20<br />

in) a = 44° 19' 36"<br />

6 = 52 29 4<br />

^ = 57 51 II<br />

sin 6 == 9'89938<br />

siu yl 9,92773<br />

C siu rt zzz: 0,1-568<br />

sin B = 9,982:-8<br />

79


80<br />

B = 1 73° 58'15'''<br />

'io6 I 45<br />

cos 6 •=. 9,78460<br />

ig^ = 0,20173<br />

tg M = 9,98633<br />

M = 44° 5' 55"<br />

sin M = 9,84254<br />

tg6 = 0,11478<br />

C tg rt = 0,01021<br />

..iu(C-j-M) = 9,96753<br />

C-j-M = 68''7" 12" efler 111° 52'48"<br />

C nzz 24 I 17 67 46 53<br />

ty 6 = o,iT4:"8<br />

cos A =: 9,72598<br />

tgM = 9,84076<br />

M =: 34° 43' 24^'<br />

cos rt = 9,85453<br />

cos M =m 9,91483<br />

C cos 6 = 0,21540<br />

cos(c —M) = 9,9847?<br />

c —M = + 15' 5'40"<br />

^ __ (19" 3"'44"<br />

149 49 4<br />

.^cr fearer C = 67''46'53" til c =: 49° 49'4",<br />

03 ligelebeg be to onbre ^BffivDicr for C eg c, ba<br />

sin yl siu C<br />

sin a sin e<br />

SJojfseg sSfltrbien 7^° "8'15" for B, ba man 67°46'<br />

53" tciii for C; r[,u cllcrg var ^-j-B-f-C < 180°.<br />

IV) rt = 39° 21'45"<br />

5 = 53 19 51<br />

C = 92 51 14<br />

tgB = 0,12811<br />

cos rt = 9,88826,5<br />

t« ^l = 0,01637,5


M = 46° 4'47"<br />

C = 1)2 51 14<br />

C-j-M = 138° 56' 1"<br />

— cosB = 9,776 12 n<br />

CcosM = 0,15885<br />

cosC+M = 9,87734"<br />

cos yl := 9,81231<br />

./ = 49° 31'36"<br />

sinM = 9,83751<br />

tgrt :=: 9,91398<br />

C sin (C-j-M) = 0,18248<br />

tg 6 = 9,95397<br />

b = 41° 58' 10"<br />

Y) rt = 44° 19' 36" o<br />

J = 57 51 II, o<br />

B = 73 58 15, o<br />

sinB = 9,9827782<br />

sin rt = 9,8443208<br />

C sin A = 0,0722775<br />

sin 6 = 9,8993765<br />

7, j 52° 29' 4" 19<br />

" (127 30 55 8r<br />

cosB == 9,4411083<br />

tg rt = 9,9897915<br />

tgM = 9,4308998<br />

M = 15° 5'39" 05<br />

siuM = 9,4156517<br />

tgB = 9,5416699<br />

Ctg^ = 9,7982646<br />

sin (c — M) = 9,7555862<br />

II.<br />

c_HI __ j 34° 43'25" 74<br />

(145 16 34' 26<br />

M = 15 5 39, 05<br />

__. j 49 49 4' 79<br />

(160 22 13, 31<br />

SI


82<br />

tgB = 0,5416699<br />

cos rt = 9,8545293<br />

tgM = 0,3961992<br />

M = 68° 7' 9" 41<br />

— cosM =: 9,5713309n<br />

CcosB = 0,5588917<br />

cos A = 9^25987£<br />

cos (C-j-M) = 9,8562097n<br />

C-j-M = 1135° 54' 4" 35<br />

' (224 5 56, 65<br />

M = 68 7 9' 41<br />

C = i ^7° 46' 54" 94<br />

(155 58 46, 14<br />

.^cr ftjare nu alter be to ferfle Sjoerbicr af c 09 C<br />

til Ijinanben, eg ligelebeg be to fibftc; tageg ben fer|](<br />

SSarbie af e, ia ma« ogfaa ben ferfte tageg of 6, h<br />

ellerg<br />

a-j-c< 6<br />

VI) A = 139° 27'35" 6<br />

B == 106 29 II, 3<br />

C == 80 37 39' 7<br />

S)et er<br />

A-\- B -j- C = 326° 34' 26" 6<br />

4-(.i-j-B-HO ^: S = 163 17_13^<br />

S — A = 23° 49' 37" 7<br />

S —B = 56 48 2, o<br />

S — C = 82 39 33, 6<br />

cos(S — B) = 9,7384278<br />

cos (S — C) = 9,1064241<br />

sin 7i = 0,0182327<br />

siu C = 0,0058364<br />

2)8,8689210<br />

cos 4 rt =r 9,4344605<br />

4rt = 74° 13' 14" 62<br />

« = 148 26 29, 24


— cos S = 9,9,812555<br />

COs(S /;'•) =Z= 9,7,^^4278<br />

C cos (N — . /) = 0,0386888<br />

Ccosi^S — C) = 0,8i)3.'",^59<br />

2)0,65194^^0<br />

tg ', 6 = 0,32,39740<br />

- 4 6 = 64- 43' 42" 28<br />

6 =z 129 27 24, 56<br />

— cosS 1= 9,9812555<br />

cos (S — C) = : 9,1064241<br />

C sin yl =: o, 1870998<br />

C sin B = 0,0182327<br />

2) 9,2930121<br />

siu 4 c z=^ 9,6465060,5<br />

4 c = 26° 18' 7" 64<br />

c = 52 36 15, 36<br />

8,j<br />

§. 22. gorfaavibt fom ofte veb cvcnftancnbc gormler<br />

^cftcmmclfcr ere gjortc gjcnnem ©inug og Sofinug, l^vilfe<br />

give SSinflcn ftunbom minbre ftffert, blive be iffe ftebfe nn;<br />

venbclige. 3 ft fanbnnt ^ilffflbe vil mnn let igjennem een<br />

cller nnben 'DD^ct^obe fomme til et vel bcftcmt 9tc|"ultnt.<br />

g. Sr. SSnr ber given<br />

rt = 23° 27' 50"<br />

6 = 25 2 58<br />

C = o 57 I<br />

bo vil c, fom bliver liben, igjennem Sofinug fun uftffert labe<br />

(ig beftemme; mca tngcg nf 'Jrionglct 5


84<br />

fffttcg ^er<br />

bo cr<br />

cot 6 r cos M<br />

cos C r sin M<br />

cos C<br />

-—- = tgM =: cosCtgfe<br />

cot 6 °<br />

sin C cot B = r sin {a — M)<br />

ligelebeg veb fomme ©ubftitution<br />

cos e zi=:i sin 6 (cos a cot 6 -j- sin n cos C)<br />

tillige cr<br />

.^crof<br />

ellcr<br />

sin c<br />

cotB<br />

= r sin b cos (jci — M)<br />

sin 6 sin C<br />

sinB<br />

cos C<br />

sm L sin M<br />

cot C<br />

= sin (rt — M)<br />

sin M<br />

sin M tg C<br />

*^ ^ {a —^:\I)<br />

enbvibere ^oveg<br />

sin c sin b sin C'<br />

tg e . -=:— : r sin 6 cos (rt — M)<br />

cose sin if<br />

sin C<br />

r sin B cos (rt — M)<br />

men<br />

nitfno<br />

sin CcosB<br />

Sin L cot ZJ = —„—<br />

sm B<br />

•=z r sin {a — M)


85<br />

tg {a — M)<br />

tg C = - ,r—<br />

cos li<br />

5Seregncg ^er nitfno Jjjffipe; SSinflcn og bcrnffft fmft B, fno<br />

Inbcr c. pg gobt beftemme igjennem fin ?;nngcnt.<br />

Snbvibcrc wfTcr mnn ofte nt i/ate en


86<br />

§. ?3- golgenbe gormler give i etf)vcrt ijilffflbe fiffw<br />

9?efultnter, fom ogfin Sontrole, eg tjcne ofte, ^vor be fort;<br />

gnocnbe gormler vilbe give minbre fiffre .^Beftcmmclfer,<br />

cos rt cos 6 cos e -j- sin b sin c cos yl<br />

TfltfOO<br />

cos rt COS 6 cos C — sin 6 sin e -j- sin b sin c -j- sin i<br />

Ctgdebeg<br />

sin (• COS A<br />

COS (6 -j- c) -j- sin 6 sin c (l -j- cos A)<br />

cos rt COS 6 COS C -j- sin 6 sin c — siu b sin e -j- sin (i<br />

So nu<br />

fofl ^nveg<br />

sin c COS A<br />

cos (6 — c) — sin 6 sin c (l — cos ^^<br />

I — cos (6 4^ '-O ^^^^ 2 sin V (6 +^ c)-<br />

I -j- cos (6 _+ c) = 2 cos 1 (6 i c)-<br />

i) I -j- cos rt 2cos 4 (6-|-c)' "f* ^'1^ '^ sine (i -j-cos^<br />

2) I -j- cos a r = 2 cos ] (6 — c)- — sin 6 sin e (i — cos.i)<br />

3) I — cos rt ^=z 2 sin 1 (6 -|- c)- — sin 6 sin C (l -j- cos J)<br />

4) I — cos rt ^^ 2 sin 4 (6 — r)- -j- sin 6 sin c (l — cos^<br />

Se^nnbleg pnn fnmme 93Jnobe<br />

cos A zzzz — cos B COS C -j- sin B sin Ccos a<br />

foo cr<br />

cos A = : — COS B cos C — sin B sin C -j- sin B sin C<br />

eflcr<br />

-j- sin B sin Ccos rt<br />

=:^ — cos (B — O ~f" si** ^ sin ^"(14- cos rt)<br />

COS A = — COS B COS C-j- slu .B sin C— sin B sin C<br />

-j- sin B sin Ccos a


87<br />

—- — cos (B -j- C) — sin B sin C (l — cos rt)<br />

nltfan<br />

I) I ^ cos A = 2 sin ; (B — C)- + S'" B sin C<br />

(l -j-COS rt)<br />

II) I -j- COS yl = 2sln 4- (B -j- O' — «'" B sin C<br />

(l — cos rt)<br />

III) I — cos yl = 2 COS 4- (B — O' — S'" B sin C<br />

(l -j- cos rt)<br />

IV) 1 _ cos ^ = 2 COS 4 (B -j- 0= -j- sin B sin C<br />

(l COS rt)<br />

5ngeg i) og multiplicercg meb i — cos A , fna er<br />

(l -j- cos rt) (i — cos yl)<br />

^= 2cos 4(6 + e)^ (i — cos^-j-s'" ^ sluc(i —cosy^^)<br />

=. 4cos 4 (6 + c)- sin 4- A' -j- sin 6 sin c sin A'<br />

multtpUccrcg IV) meb i -j- cos«, fnn er<br />

(l -j- cos rt) (l cos yl)<br />

= 2 COS 4 (B + O^ (l + cos rt) + sin B sin C (l - cos rt^)<br />

=: 4 cos i(^B -^C)'' COS 4 rt^ -f- sin B sin Csiu rt^<br />

nitfno<br />

4COS 4- (6 -j- c)' sin 4- A^ -j- sin 6 sin c sin A"^<br />

= 4C0S 4- (B -j- C)^ cos 4 "^^ -j- sin B sin C sin «'<br />

sin B sin C sin rt^ :E= sin B sin rt X ^in C sin rt<br />

Stgdebeg<br />

sin 6 sin c sin A^ ~~~ sin 6 sin ^ X sin e sin ^<br />

3tItfao ere biffe to ©tfiirrdfcr ligeftore ifelge §. 17 3.<br />

felgdigcn ogfoo<br />

4cos4(6-j-c)2sm4.^' = 4cos4 (B-J-Q'cos S-rt'<br />

oltfao<br />

CCS 4 (6 -j- t-O sin i A = cos 4 (B -j- C) CO? 4^ «


88<br />

"Poo fomme 5)Joflbe, ^vig 2) forbiubeg meb ll), ct;-<br />

folbeg '<br />

cos 4- (6 — c) cos V yl = sin 4- (B -j- C) cos V a<br />

3) meb in)<br />

sin 4- (6 -j- c) sin 4- A = cos ! (B — C) sin 4 rt<br />

4) meb II)<br />

sin 1 (6 — c) cos 4- A sin 4 (B — C) sin -J rt<br />

ellcr tilfommen<br />

I) sin .J (b -^ e) sin 4- yl cos 4- (B — C) sin 4- rt<br />

II) cos 4 (6 -j- c) sin 4 ^7 = cos i (B -f- C) cos 4 rt<br />

III) sin 4- (6 — c) cos 4- yl = sin 4 (B — C) sin 4 a<br />

IV) COS 4 (6 — c) cos 4- ^-i = sin Y (B -j- C) cos 4 rt<br />

Src nu 6, c, A givne, ba cr 2(lt poo f)eirc ©tbe nf<br />

Stg^ebg;5egnet befjcnbt, pnn venftre ©ibe ubcfjenbt, om;<br />

venbt ^vtg B, C, a,- olle Sele finbeg fnolcbeg poo eengnng.<br />

2t It nj.


89<br />

1) sin \ (6 -j- c) = 9,61 jf'i.-, 3) sin ', (6 — c) = 8,14103<br />

5) siu 4^'/ = 7,9 u'.ro 6) COS,; ./ = 9,99999<br />

2) COS \ (6-j-c) = 9,Q,TI;S6 4) COS 4(6 — c) = 9,9999^<br />

6. 4. IV. 9,9-;no3 3- 6. 1. 8,14101<br />

9,09c;vg 9,9t^7-'3<br />

5. 2. 11. 7,8.-636 I. 5- M- 7,333.^5<br />

tg ; (B -j- O = 2,72T39 tg 4 (B — C) = 0,60866<br />

sln4-rt = 8^79 '.(B+C)= 89" .34' o" 5<br />

COS 4rt = 9,99996 4(B —C)= 71J 10 2<br />

8,15383<br />

Sin Vrt = 8,15379<br />

4 rt = o 48 59' 4<br />

B = 165 44 2, 5<br />

c= 13 23 58, 5<br />

cos V rt = 9/99996 a= i 37 58, 8<br />

gor t>:t 5ti;^cf.<br />

B = 107" 17'15"<br />

C — 93 20 30<br />

rt := 112 20 59<br />

B -i- r = 200" 37' 45"<br />

B — C = 13 56 45<br />

4(B-j-O == 100° 18'52" 5<br />

4 (B — C) = 6 58 22, 5<br />

4 rt = 56 10 29, 5<br />

])sln4(B4-0= 9,992924 3)6!n4(B —C)= 9,084219<br />

5)cos4rt =9,745590 6)sin4rt = 9,91946.^;<br />

2)cos4(B-(-C)=9^25298in 4) cos 4(B — C)= 9,996776<br />

4. 6. I. 9,916241 3. 6. III. 9,003684<br />

9,996850 9'992758<br />

5. 2. II. 8^8571^ 1-5- IV. 9,738514<br />

tg i- (6 4- c) = o,9i7670n tg ; (6 — e) z= 9,265170<br />

sin 4^= 9,919391 4(7,4-0= 96° 53'31" 5<br />

cos 4^= 9 745756 4(6_r)= 1026 2,7<br />

tg4^=^i736^ -/= 5


90<br />

3cummcrnc, ber ftaae foran, tilfjenbegioe, i ^oilfen<br />

Otben Dicgningen flal forctagcg.<br />

DBcrccngftcmmclfen mellem gstsrbierne t ferfte ereiti;<br />

pel eg 93(srbierne funbne §. 22 oife iReiagtigbeben, fom<br />

igjennem paffcnbe gormler meb 5 Secimaler Ean fil^ob<br />

beg. Sn neiere aseregning meb 7 ®ecimalcr gioer<br />

B = 165° 44' 2" 45<br />

c = I 37 58, 96<br />

Senne faalebeg albcleg neie Doerecngficmmelfe er Ml<br />

et St)fEctr«f ber, bog ril gotffjctlen iffe let beWe fij<br />

tit meet enb faa ©ecunber.


§. I. vDfuOe 'Potcnfer of famine Slob multiplicercg,<br />

bo (Tecr bette, naar Srpo"«»terne obbereg; t^i f (£r. a"" er<br />

egentlig a X a X a... a D: a fat m ©ntrge fom gnctor; a'^<br />

cr a fat u ©anij.e fom gactor, oltfao a'" X a" er a fot m4-u<br />

fom gactor, ellcr a + ''-<br />

§. 2. ©futle fpotenfer of famme 3\ob bivibereg, bn<br />

tubtra^ereg (Srponenterne, f.Sr. a^ ec a X a X a X a X a,<br />

a^ aXaXaXaXa<br />

a' cr a X a X a, oltfoo — = = aa'<br />

a Xa X a<br />

cller t ^Uminbclig^cb er — z= a'"—"<br />

Sill. I. Set tnbfeeg nu, ot, noor n er fterre cub m,<br />

en negativ Srponent fremfommer, l)vilfet iffe bcti;bcr anbct,<br />

enb Sen^ebcn, bivtberet meb fnmme 'poteng, men meb pofi;<br />

a^ I<br />

tiv Srponcrt, fnnlebeg er — = a' — * ^= a—* z= —<br />

a* a^<br />

I<br />

eg a—p = —<br />

^ ap<br />

Sill. 2. Sre Sivtfor og Sivibenbug fnmme


92<br />

= a" = I; eller ^vtlfcnfomr^clfl ©tm'clfe op^ciet til $oi<br />

tcnfcn o er ligcftor meb i.<br />

§. 3, ©fnl en *Poteng otter op^eieg til en ^otenS,<br />

ba multiplicercg beng Srponent meb ben nt;e *petenfeg Srponent,<br />

f.(£r. 0'"")'^ = a'""; t^i (a'")" er a"" X a'" X a'".....a"",<br />

beftanenbe nf ngocto.-cr, olle ligcjtore meb a ellcr a'""<br />

S; i 11. I. ©fal ct 'Probitct nf v''otcng;©terrclfer o|)i<br />

^eicg til en ^otcng, bo ep^eieg ^ver gnctor for fig til "Po;<br />

tcnfei^.<br />

St If. 2. ©f'll cn Cvotient af 'Poteng;©t0rrclfet<br />

eller en SBr^f, ^vig ^ffller og 3iffvncr ere 'p>orcng;©t0rrelfe<br />

op^uieg t


93<br />

ben fnn ubbrngcg, og cn nnben, lyocvaf bet iffe fan fFcc, og<br />

ubbrngeg Jiiobcn af ben fuvftc; I;cvvcb ubtn;ffcfi S'lODftirvri-ifcn<br />

ftmpleve. g.ti.v. VTi = 7^9X2^= ^9X^2 = 3^2<br />

Sill- 2. 3lltfan Eu:;nc j^OLftarrdfcr of fammc 9?eb<br />

multiplicercg ellcr bivibereg meb f)inanben, naar ©tstrclfcrne<br />

unbcr Diobtcguet multiplicercg dice bivibereg og bevnfffc givcg<br />

bet ffftkbg 31ottojn.<br />

'Jilt. 3. ©fulle nltfan 9\obft0rrcll"er multiplicercg<br />

ellcr bivibereg meb ^innnben, fom iffe ere nf fnmme 9tob,<br />

fnn mane be bringeg bertil ellcr bringeg til eeng SScno'V;<br />

jiing. Scttc fTcer, nnnr for 9vob;(£-rponcntcrne fogco bet<br />

fffllcbg beldige "Snl, ^vcr cnfelt 9Iob;£rponent bivibereg l)eri,<br />

og meb bet fom ubfomuer, multiplicercg fnnvcl 9Iob;(£rpo;<br />

ncntcn, fom 'Potcng;Srponcnten nf pallet unbcr Slobtegnct.<br />

_ 3 _ 6 6 6 6<br />

g.£r. V^3 og Vs ere V3' og Y5- eller y27 og Y^25;<br />

felgdigcn multiplicercbe V^675, bivibercbe Y^l<br />

§. 6. ©fill en 9tob ubbrngeg af en 3iob;©t0rrclfc, ba<br />

multiplicercg 9Iob;(£rponentcn meb ben ni;e SHobg (Srponent.<br />

Slobfierrclfcn, fom l)crveb fremfommer, vilbe ncmlig, op;<br />

l)eict til fnmme


94<br />

§. 7. Ubbrngeg en lige 9Iob of en pofitiv ©terrclfe,<br />

bo fnn ben fnnvcl vffre pofitiv, fom negntiv; t^i fnnvcl cn<br />

pofitiv fom negntiv ©tKrclfe, epf)eict til cn lige 'potcng,<br />

frcmbringcr en pofitiv ©terrdj'e, fnnlebeg cr Y^i6 = +3<br />

Sn lige 3lob berimob of en negativ ©torrdfe cr ftebfe<br />

cn uinultg ©t,errelfc (I. §. 115), ^vig olmiubclige govra bW,<br />

2n<br />

ver Y— a. Sn foobon ©torrdfe lober fig ftebfe bringe til<br />

a n_ 211<br />

Ya X V^—1/ ^tjorvcb ben (TiL'cg t te gactorer, een mulij<br />

eg een umultg.<br />

S i t f. I. Y^ X Y^ = (^~iy: = -I,<br />

bet inbfecg nu, ot Y— a X Y— b = — VaL, bn Y—i<br />

=z: YaX V— I eg V— b A'^b X V— i.


2/5 —v^Ti<br />

95<br />

^ev cr nu ferft V'lS = V^9 X 2 = 3Y'2 (§. 5<br />

5ill. i). 5.ltultiplicereg i 'Sffllcr og 37ffvncr meb 2Y^5<br />

-f-3Y^2 o: meb 37ffvncren meb olle 'Jcgn, foranbrcbe, bet<br />

ferfte unbtogcn, fnn cr<br />

3Y'5-2\^2<br />

2>^5 + 3>^2<br />

30 —4^10<br />

4-97^10 — 12<br />

3o4-5V^io—12 = i8H-5V^io<br />

Sigclebeg Vffre given:<br />

2V^6 4-3-/T^<br />

2Y~2 -Yl-j-Ys<br />

53Jultipltccrcg i Sffllcr og 3?ffvncr meb 3V^2 -j- V3<br />

— Y5, bliver 5ffUcrcn 6V12 -j- 9Y^2D -j- 2V^78 4- 2,Y^<br />

— 2Y'^-^YTo z= i2Y^+i8Yl + 6Y2-\-Y^<br />

— 15Y2 = i2V^i4-i8V5 —9V"2 4-'f35<br />

S^ffvneren er<br />

(zY'2-Yl-\.Yl)i'iY2-^Yl-Yl,)z=:z 18-3<br />

4-2^^15 — 5 = io4-2Y^i5<br />

3tltfnn 95refen ligcftor meb<br />

12 V^3 -j- 18 V^5 — 9 V2 4- V30<br />

I0-f-2V^l5


96<br />

9]tUltip!tccreg nu ntter i ^fftler 05 37ffvner meb 10<br />

— 2V^i5, fnn er 'JffUcrcn:<br />

120V3-j-1 SoV 5 — 9oV^2 4-loV 30 — 24V^45 — S6V75<br />

-j-18V^30 —27^450 z= i2oV^3 4-180V5 —9oV^2<br />

4-ioV^30 — 72Y5 — iSoV^S 4" 18^30 — 3oV^2 =<br />

— 6oV^3 4-28 V30 — 120^^24- 108 V^S-<br />

3flffvnerctt (10-j-21/^15) (10 — 2V^i5) = 100—60<br />

= 40. 3(ltfofl cr f)cle S5r,pfcn rcbuceret.<br />

•ruY^ — TY'i — 3YZ+UY5<br />

'Pnn fnmme 93innbe forctngeo Sicbuciioiien nicb imngi;<br />

nnire ©teirrelfer, fom ere bivibercbe meb ^innnbcn.<br />

g.Sr.<br />

5 Zl^GzZ - (5 - '^^^) (I — '^^^) ^ 3-6V^^<br />

i4-^^^ (i4-'V^^)(i —V^) 3<br />

= I —2Y'^<br />

jjervcb erinbreg, ot V'— i X Y— i = — i, nit*<br />

fan f Sr. t SHffvnercn Y— 2 X — V^— 2 = — (/—2<br />

xY^^2) = -(-2) = 4-2<br />

S?nr 3?ffvncren cn trelebbct ©torrdfe, ba i)avbe in<br />

Vffret nebvenbigt, enb eetignng ot forctogc O^iultiplication i<br />

Iffller og 97ffvner, ^vorvcb bet ^moginoire olbdcg var fov;<br />

fvunben of ben (ibfte.<br />

§. 9. ^nve vi cn tolcbbet ©tar.clfe, bcftnaenbe nf cn<br />

rntionnl og cn gvnbrntifT trrntionnl ©tin-rclfe, eg nf benne<br />

a.vnbrntrobcn fTulbc iitb-u.-icS, ba vnr bet ftunbom muligt


97<br />

bcrveb nt forctnge cn StebHctien, fom (ctrbtliycii Ictu-ie ^U'v)-<br />

uingcn.<br />

Sen olmiubclige gorm for et faabant r.btn;f var<br />

•f (A + Yh)<br />

Seclte vt ClvabratjCEttvactioucn i to Sele, og fattc nit;<br />

fnn ltbtri;ffct<br />

= Yx + Yj<br />

fnn, ^vig ter gvnbrevebcg paa he^?,e ©i^cr, cv[;cIi.tco<br />

A±"V^B = x + ^y^-l-y<br />

Sa nu pan beggc ©iter en rntionnl og cn itfnttonnl<br />

Seel finbeg, fnn ^nve vi<br />

A =1= x-l-y YB = 2Y^<br />

nf ^vilfe 2(S(|vntioncr >i og y bcftcmiueg.<br />

Sen fibfle giver<br />

B =<br />

Sinbfffttcg ^ert<br />

4xy<br />

y =<br />

fnn er:<br />

A —X<br />

4Ax —4x= = B<br />

Qlltfnn<br />

x= — Ax = — iB<br />

gor at gjere benne qvabrntifTe ?(Sqvntion fulbftffnbin,<br />

obbereg pnn beggc ©iber 4A-, nltf'ao<br />

x'—Ax-j-iA= = i(A^--B)<br />

ipvoraf<br />

X —^A = +IYA^—B<br />

X = KA + VA'^ — B)<br />

ijeraf ubicbcg<br />

y = 4 (A + y AJ^^O<br />

II.


98<br />

Smiblcrtib, bo bet er vilfnorllgt, ^vab vi falbe x og ^vob y,<br />

ville vi ftebfe bc^olbe be fl^verfte 'Segn. Jlltfnn cr:<br />

y(A + yB) = VKA4-VA^-B) + Y'4(A-yA^-B)<br />

Senne gormel giver ftebfe 3lffortncng, noor V^A-—B<br />

er rntionnl.<br />

%nm. ©oiu €remplcr vtsre gione:<br />

I) v"a4-'v^2)<br />

.^cr er VAT^^ = Yi — 2 = Yi = h<br />

ailtfao<br />

^(44-^2) = ^i(^4-i) + v^a-^)<br />

= i4-"V4<br />

II) V(28 4-5V^) _<br />

j^er cr A = 28, B = (5^12)' = 300,<br />

altfaa A=—B = 484, bvoraf aoflbratroben cr 22,<br />

altfaa Ubtri)lfet ligcitort meb<br />

^^4-^3 = 54-Vi<br />

III) 7^(87 — 12-^42)<br />

^cr cr YA"" — B = 39<br />

SMltfaa bliver Ubtrpffet<br />

^63 — ^^ = 3^7 — 2^6<br />

IV) y(VT8-4) _ _<br />

X?cr maae vi f«tte VB = 4; A = V^iS, bi<br />

ctferg yA- — B btco iinaginair; r.u cr ben ligeitor ntei)<br />

Y2. gelgcligcn bliocc Ubtrpflet<br />

V(!.- iYTs 4- V2)) — ^(4 (YTs — Y2))<br />

SKcn, ia Yl^ = 3^2, erl)olbcg<br />

Y2Y2 — YY2 =:Y8 — YZ


99<br />

§. 10. (Sn li;3nenbe ,^oi;r.l (•^er fig ubvifle, l)via<br />

0.vatvaticB;Srtractioncn ffulbe forctagcg of et 9?inomium,<br />

fivig ene Scd var i m fl g i n n i r, lunfor blcv ben niminbc;<br />

lige gorm<br />

Y(\ ± y^B)<br />

©ffttcg bette Ubtrijf ligeftort meb Ys. ± V—y, fna var<br />

X —y = A<br />

2Y—XY = Y^^^<br />

ellcr<br />

4 xy = B.<br />

Snbfffttcg l;cii x = A -j- y, fnn er<br />

B = 4Ay4-4y^<br />

^votaf<br />

- y^-j-Ay = iJ^<br />

oplefcg benne qvnbvntift'e vcqvattou, fnn cr<br />

y = — 4 A + Y'A=4-B<br />

X = 4A+ yAr="4^<br />

jpcr funne vi ntter tnge bet evcrfle Scgn, ba cv:<br />

Y(A+Y^) = Y -\(_A+YAX^) + YliA~YA}'^)<br />

51 nm. ©om Crcmplcr v«vc girnc:<br />

I) ^(7 + 6^-"^)<br />

jjier cr A^-j-B = 494-72 = 121, I)rovaf Gva-bratroben<br />

er n; altfaa Ubtvi)ffet cr 34-V—2<br />

©aalebeg er<br />

II) Y(-2-2Y^T5) = Yz-Y^<br />

III) Y"—"64 = ^(0 4-^—64) = 24-2"/"^<br />

IV) Y(- y —7) =1 Y(p—"f-7) = Yi -\- Y^s<br />

§. II. goruben be (I. §, 102-121) opleftc S^qvatio;<br />

ncr, Inbe cnbnu olle ^eicre rcne Q^qvntioncr fig opl^fe. i^mvcg


fno cr<br />

oltfno<br />

100<br />

ax .n-j-l"^" = c-j-dx"<br />

(a-j-b — d) x-i = c<br />

a -j- b — d<br />

n<br />

a-f-b —d<br />

§. 12. OPS. >f?wlfct 5nl cr bet, ^vig i?olvpait,<br />

^rebicpnrt, gjerbepnrt multiplicercbe meb l)vcranbre og 'Pwi<br />

buctet foreget meb 32 giver 4640.<br />

•Snllet Vffre x, fna cr<br />

4xXixX^x4-32 = 4640<br />

^x^4-32 =: 4640<br />

z:Vx' = 460s<br />

x^ = 110592<br />

3<br />

X ^= Yii05


lOI<br />

§. 14. Op3. ffliflii fsgcr to Zal, ^vig 'Probuct er<br />

3(;o, bereg (£ubcrg ©um cv 17199, ^vilfe ere 5;nllenc?<br />

xy = 360 x' -f-y' := 17199<br />

360 , , /'36o^^'<br />

y = —• X' 4- ( — J = 17199<br />

Jlitfnn<br />

x^ 4-46656000<br />

-1 = 17199<br />

ft<br />

..•Her<br />

93Jultipliccrcg meb x% fnn ^nvcg<br />

x'^ 4-46656000 = 17199X*<br />

x'^ — 17199X' =:= —46656000<br />

©ffttcg nu x^ = z, fno ^nveg ben urene qvnbvntijTe<br />

J@qvntion<br />

z^ — 17199Z =^ —46656000<br />

)enne gjercg fulbftffnbig veb bertil nt feie<br />

'jvornf<br />

(<br />

3?u er otter<br />

^erf it fvorer omvenbt<br />

( 17199^' 295805601<br />

2 J ^<br />

^_I7I99'\^ ^ 09181601<br />

4<br />

17199 + V109181601<br />

3<br />

X = Y'z<br />

(13824<br />

( 3375<br />

(24<br />

{15<br />

(24<br />

2


102<br />

§• 15' Opg. S>er er gtvct ct retvinflet '5:riongcl,<br />

betg glnbe;3inb^olb cr 30 Clvnbrntfob og Jpi;potenufen er 13<br />

gob Inng, f)Vor ftore cre Sot^ctevne.<br />

€nt^ctcrue Vffre x og y, fnn er glnbc;3inb^olbct ligc;<br />

flor meb 4 xy (I. ©com. §. 144 5tll.), Jjt;potenufen =<br />

Vx^-j-y-, oltfnn:<br />

^^ i^y =^ 30 H) x^4-y^ z= 13^<br />

xy = 60 = 169<br />

60<br />

y<br />

5inbfffttcg benne SSffrbie t H), fnn er:<br />

GUcr<br />

J^ernf<br />

2fltfao er<br />

y^<br />

(l°)*+y' = .6,<br />

3600-j-y = 169 y'<br />

y^-i69y^ := • — 3600<br />

169 _j_ V1416<br />

2 3<br />

(M4<br />

^' == 25<br />

2856X<br />

4<br />

i= + 119<br />

2<br />

Set cr: for y finbeg felgenbe fire SJffrbier: 4-12, —12,<br />

4-5^ — 5-<br />

Sinbfffttcg biffe i Ubtri;ffet for x, ubiebet of I), faa<br />

er x lilfvorcnbe bertil: 4-5, —5, -j-12, —12.


103<br />

Sn bet fommer an pnn cn gcomctviff ©terrclfe, vil<br />

^cr orbentltgviig iffuu tngcg be pofitive Dpiegniuger, ellcr<br />

©vnrct bliver: ben cue Cnt^ctc cr 12 gob, ben onben 5 gob.<br />

§. 16. .Jjnvcg (Srponentinl;2eqvottoner, bet<br />

er fonbnnnc, l)voci ben ubcfjenbte ©terrclfe forefommer fom<br />

^rponent; bn Inbe biffe fig oplefc vcb Sognvit^iucr. Sen<br />

nlminbdige gorm, ^vortil be Inbe fig bringe, cr:<br />

Stltfno<br />

^vorof<br />

a^ = b<br />

X log a = log b (I. §. 126)<br />

. log a<br />

logb<br />

€rempel ^crpoo er Oplegningen of n (I. §. 129).<br />

§. 17. OPQ- 3 cn Solonie formercr golfetotlct (Ig<br />

onrligt -^, ^vorlffngc vnrcr bet, inben Snbb^ggcrneg 5lntfll<br />

er forbobblet.<br />

/jer cr S^qvntioncn<br />

©" =<br />

x log — == log 2<br />

^10 =•<br />

x.0,04139 = 0,30103<br />

ijcrnf<br />

0,30103<br />

X = = 7,273<br />

0,04139<br />

eacr 2l'utallet vil vffre forbobblet omtrent c 7 2(ar 14 Uger.<br />

§. 18. Set er oUcrebe for^en bemffrfet (I. §. 114),<br />

ot, nanr en Opgnve afgiver et minbre 3tntnl Signingcr, enb<br />

ber finbeg Ubcfjenbte, benne er bn ubeflcmt (indetcrmi-<br />

natum). ^miblcrtib funne ^nbffrffnfningcr vcb Opgnven


104<br />

finbe ©teb, fom gj^re, ot nf be mnnge Oplagning^r, fom<br />

egentligen givcg, fung fnne, eller en enefle, eller vel cnbog<br />

albcleg ingcn tilfccbgfliller Opgnven. Sremplcr ^crpnn, font<br />

og "K'anbcn nt oplefc faobnnnc Opgnver og nnvenbe be til<br />

benne Siegning pnffcubc ^unftgreb, ville felgenbe Opgnvct<br />

nfgive.<br />

§. 19. (in 5Sonbcfone ^nr ^jemmefro mebbrngt 200<br />

SSblcr, unbervcig ffflger ^un nogle, inen bog iffe Jpnlvpav;<br />

ten; bo ^un fommer til 5Si;en, veeb ^un iffe, em ^un f!al<br />

fixlge bcm i ©nefe; eller i Seufinviig; t^i t ferfte 'Jilffflbe<br />

bef)olber t)Urt 14, t onbet 10 ©tfr. til Sveft; ^vormnnge<br />

^nvbe f;un ?<br />

Sjibftc vt enten, ^vormonge ©nefc eller ^vormnnge<br />

Soufin ^un ^nvbe, bn var 'iintnllet let ot beregne; vi falbe<br />

oltfna ©nefeneg "Untal x, Soufincneg y, fno ec Sublet;<br />

neg lal<br />

20X-J- 14<br />

ellcr<br />

i2y4-io<br />

nitfno<br />

20 x-j- 14 12 y 4- 10<br />

Jpcrnf<br />

5x —3y = —I<br />

Sn X og y nu tfi'lge fin S'lntur ere ^cle og pofitive 'Sal,<br />

fnn, ^vig vi oplofe 3(*qvntioncn, fom om beri y vnr ben<br />

enefle Ubcfjenbte, fnnbteg<br />

5^-t-i .2 x-j- I<br />

i o<br />

2x4-1<br />

jjvor bo ntter -— er et ^oelt Hal, fom vi viHe betegne<br />

meb z, oltfao


dice<br />

X<br />

2x4-1 = 3^<br />

3z—I z—I<br />

J " ^ I ;<br />

105<br />

2 T<br />

nu cr igjcn ct t)cclt Sal, fom vi ville betegne meb -a,<br />

2<br />

l)vovnf<br />

Z Z= 2 U 4" I<br />

X = 3 ll -+- I<br />

y = 5 » -1- 2<br />

a^ilbc vi alifaa bcftcmme SSblcrneg 3lntn!, blcv bette i<br />

Sonfinviiu<br />

Sigclebeg eftcv ©ncfe<br />

©ffttcg nu<br />

evt)olbcg ^Intnttct<br />

12 y 4" 10 = 6o u 4- 34<br />

20 X -j- 14 == 60 U -j- 34<br />

= 34' = 94' = 154/ = 214<br />

Sc to ferfte 5Scittcv ere for fmnne, bn ^un ^nr mccr enb<br />

jjnlvpnrten tilbngc o: 100, ben fjcrbe og be felgenbe for<br />

flove, ba ^un ^nr unber 200; vi funne oltfao ene outage<br />

fom Oplegning 154.<br />

§. 20. Opg. 30 'Perfoncr, tOiffnb, .Soner og<br />

S&ern, fortffvc tilfninmcn 50 Stbblr., en 3)tnnb betnler 3<br />

9?bblr., cn ^one 2 9Ibblv., et SSncn i 3vbblr.; ^vormnnge<br />

^cvfoner vnre nf ^vcrt ©lagg?<br />

Jper cr, nnnr SlJffnbcneg 3fntnl er x, ,^oncrncg y,<br />

Serncneg z:<br />

x4-y-fz = 30 3x4-2y-fz = 50


io6<br />

veb nt fubtrn^ere ?@qvotionertte frn ^innnben, cr^olbcg<br />

2 x-j-y = 20<br />

oltfnn<br />

20 — y<br />

Sn y iffe fnn vffre negntiv, fnn fnn x iffe Vffte ft^tte<br />

enb 10, og y ligelebeg iffe fterre enb 20, nnor x ffnl VOTC<br />

pofitiv; men man forreften vffre et ligc ^nl, for at x iffe<br />

(To! blive SBref; nnor oltfao y cr valgt, er .?5ernencg 3tntal<br />

be|temt; eller vi fane<br />

tOiffub: 10, 9, 8, 7r 6, 5, 4, 3, 2, I, 0<br />

^oncr: o, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20<br />

aSern: 20, 19, 18, 17/ 16, 15/ i4/ i3/ 12, 11, 10<br />

Sen ferfte og ben (ibfte Oplegning funne egentligen<br />

itfc brugcg; men be evrtgc cre olle lige ontogclige.<br />

§.21. Op9. ^'^ tiebex 100 ©tfr. Clvffg for 400<br />

9?bblr.; for en 0;:e betoler ^on 40 3ibblr., for en ^ee 20<br />

Svbblr., for cn ^alv 8 Sibblr., for ct Som 2 SKbblr. jjvov;<br />

monge of ^vert ©logg?<br />

Jjcr ere S^qvattonerne<br />

I) x-j-y-j-z-j-u = 100<br />

II) 40 X -j- 20 y 4- 8 z 4- 2 u ::= 400<br />

eller<br />

20x4-ioy4-4z4"ii =^= 200<br />

nitfnn<br />

i9^x 4-9 y 4-3 z = 100<br />

X I<br />

z=33 — 6x—3y -^—<br />

5DJen, bo z er et ^eelt "Zal, mnne vt funne ffftte<br />

X — I<br />

• = V, fom otter er ct onbet hecit ^nl.<br />

3<br />

2


3iltfnn<br />

X = 3 V 4-1<br />

^nbffftteg benne 23ffrbie, faa er<br />

z = 33— i8v — 6 — 3y — V<br />

= 27 — 19 V — 3 y<br />

107<br />

V og y funne togeg vtlfnnvligt, bog fnnlebeg, nt z bliver<br />

pofitiv, nitfnn I9v4-3y iffe flerve enb 27; ci fjcllcr mnn<br />

V vffve negntiv, ba ellcvg x ogfaa blcv negativ. ©nalcbcg<br />

fnn fun v vffvc o ellcr i. dlu or:<br />

V O V = I<br />

z = 27 —3y z = 8 —sy<br />

u = 72 -j- 2 y u =z: 88 -j- 2 y<br />

SSffvbicn for u er ubiebet nf 2@qvntioncn I).<br />

X<br />

y<br />

z<br />

u<br />

X<br />

y<br />

z<br />

3(ltfan ere fun felgenbe Oplegningcr mulige;<br />

gor V = 0<br />

I, I, I, I, I, I, I,<br />

0, I, 2, 3, 4, 5, 6,<br />

07, 24, 21, 18, 15/ 12, 9,<br />

72, 74/ 76/ 78/ 80, 82, 84/<br />

4/ 4/ 4<br />

0, 1, 2<br />

8, 5/ 3<br />

u I 88/ 90/ 92<br />

gor V =; I<br />

1/ I, I<br />

7/ 8, 9<br />

6, 3/ 0<br />

86, 88, 90<br />

55ortfnfle vi be Oplegninger, ^vori forefommer o, blive fnn­<br />

lebeg i 3llt 10, fom tilfvebgftille Opgnven.<br />

§. 21. 3ff ct €ompngnie, fom er onfnt til 200 93innb,<br />

fnvneg cn Sec! efter en SJatoiHc; Sompngnte;£f)efcn bliver


108<br />

nbfpurgt, eftcrnt Sompnguict ftben vnr Mcven opleft, f)vot;<br />

mnnge 93Jnnb, ber vnre blcvne tilbngc, men fnn iffe erinbre<br />

fig bet; Ijan f)ufTer berimob, ot, ftror cfter SBotoillcn, gjotbe<br />

f)nn et gorfeg ot Inbe bcm ftille ftg i ©elebber, men ftebfe<br />

forgjffvcg; t^t ftillebe ^nn 2, 4, 8, 10 'iStnnb i ©debbct,<br />

^nvbe ^an ftebfe i 5[)fnnb tiloverg, ftillebe ^nn berimob 6<br />

cller 12 5]Ionb, ^ovbe ^an ftebfe 5 SJonb tiloverg; ^vot<br />

(tort vnr Eompngnict?<br />

Opf. Snb ©ciebberneg 3(ntal vffre p, (j, r, s, t,<br />

u, Sompagntctg x, fao ^nveg:<br />

I) 2 p 4- I = X<br />

II) 4 q 4- I = X<br />

III) 8 r -j- I = X<br />

IV) 10 s 4- I = X<br />

V) 6 t 4- I = X<br />

VI) i2u4-5 = X<br />

gorcneg IV) eg VI), f)nvcg<br />

12114-5 — 10 s-j-1<br />

12 u-j- 4 ZZZZ 10 s<br />

6 u4-2 = 5 s<br />

U-^-l<br />

u4-2<br />

^er mon vffre et ^eelt lal, fom vt viKe betegne meb<br />

5<br />

A, bernf felgcr<br />

u = 5 A —2<br />

Sinbfffttcg benne SSffrbie i \I), fnn cr<br />

Jjvornf otter<br />

X =: 60 A — 19


p == 30 A — 10<br />

]iOU ba r cr ct l;celt "Sal, inan ogfan vffre<br />

ct ^edt 5al, fom vi ville betegne meb B, nltf'no<br />

A = 2B4-1<br />

X := i2oB-j-4r<br />

3nbfctic5 nu for B cfter 0^::nin aSffvbierne o og i,<br />

fan cr x enten 41 eller 161, fom eve be enefle mulige 2Sffr;<br />

bier, ba X cv unbcr 200.<br />

§. 22. Op9. So ^elc og pofitive 'Snlg ©um og<br />

'Pvobuct er tilf'nmmcn 79; ^vilfe cie 5;nHcne?<br />

Opt. 'Snllcne vffre x og y, fnn cr<br />

xy-fx4-y = 79<br />

:jfltfnn<br />

^ 79 —y _ . 80<br />

"" y-H-i ^ y-fi<br />

Scr frffveg altfnn, nt y -j- i ffnl riffre ct 5]innl for 80.<br />

Sn, nanr vi oplefe 80 i fine eufclte gnctorer, vi ^nve<br />

2X2X2X2X5, fnn cre nlle iOinnlene for 80:<br />

jjvortil bn fvnve<br />

y<br />

X<br />

i|2J4|5|8|io|i6|2o|4o|8o<br />

0 1 I<br />

79139<br />

3<br />

19<br />

4<br />

15<br />

7<br />

9<br />

???cn bn be fibfle Oplegninger blive overeengftenimenbc meb<br />

be fi.uf:c, givcg egentligen fun felgenbe 5 Oplegninger<br />

o I<br />

791S^)<br />

9<br />

7<br />

15<br />

4<br />

19<br />

3<br />

39<br />

I<br />

79<br />

o


no<br />

Sill, ©fjenbt 5


Ill<br />

gor nt gjere benne rational, ville vi ffftte ben<br />

= x4-p<br />

Sn cr<br />

I-j-X" =^ X- 4" 2 Xp-j-p'^<br />

/;vornf<br />

X = ^ ~ r'<br />

2p<br />

©fal X Vffre pofitiv, bn man for p tagco en egentlig<br />

5:n-ef, vi ville altfaa ffftte<br />

m<br />

fan er<br />

n- n-—m^<br />

2 m 2 mn<br />

11<br />

= J I 4- (<br />

^ V 2 mn<br />

)<br />

y<br />

= n^ 4- m^<br />

^vor nu ^vilfefoni^dft 'Snl funne fffttcg for m og n.<br />

Sill. 2}i funne til benne Opgnve ^cnferc felgenbe:<br />

nt fege to Ovabrntcr, ^vig Sifferentg ntter cr et Ovnbrat;<br />

eller<br />

x=—y^ = z-<br />

^voraf<br />

— CO"--CD' I<br />

vi ville for .^ort^cbg ©fi;lb ffftte<br />

ba er<br />

X<br />

z<br />

n- -<br />

z<br />

"— I •—'— I<br />

u = "V^i 4-1<br />

t, fan er


112<br />

5tltfao ffftte vl<br />

foo er<br />

bo ec<br />

So nu t<br />

u<br />

n^<br />

n'^-j-m'<br />

2mn<br />

y X<br />

: -, u = -, foo funne vt ffftte<br />

z z<br />

X := n= -j-m^<br />

2 mu<br />

x^ — y^ = z^<br />

SSi funbe egfoo poo fomme 9)Zaobe ^nve fegt<br />

x = y^-l-z^<br />

Set cr to Q,vnbrntcr, ^vtg ©ummer vnr nner et O.vobr«t.<br />

Snbfffttcg for m eg u forfTjcllige SSffrbier, fao fan<br />

berof X, y, z beftemmcg. g. Sy.<br />

m<br />

n<br />

X<br />

y<br />

z<br />

I<br />

2<br />

5<br />

3<br />

4<br />

I<br />

3<br />

10<br />

8<br />

6<br />

2<br />

3<br />

13<br />

5<br />

12<br />

I<br />

4<br />

17<br />

15<br />

8<br />

3<br />

4<br />

I<br />

5<br />

25 26<br />

7 1,24<br />

24 10<br />

2<br />

5<br />

29<br />

21<br />

20<br />

3<br />

5<br />

34<br />

16<br />

30<br />

4<br />

5<br />

41<br />

9<br />

2(nm. I. 5i5«tbicrne x, j, z afgirc ifelge ben p^tljtfgC;<br />

rifle ©cetning ©iberne i ct rctoinflet Sriangel.<br />

21 nm. 2. Set Dvenanferte (§. 18-23) maa tjcne fom<br />

spreoc paa be gjfetbobcr, man anuenber i ben ubeilcmte<br />

SInalDtif cller biopbantiffe 9lnal«fig. SJibtleftigere Unbet:<br />

vetning l)ercm baoeg if«v i Sulerg algebra, l)ril><br />

fet cIcinentCBve Ssoerf, i govbinbclfe meb Sag range's<br />

Silfffitninger, tjener fom cn Ovcrgang til be vanflclijiere<br />

asoirf i benne ffltatevie.<br />

goruben ben franfle Ubgave tjaveg cnbnu of SiilcrJ<br />

saigebra et Ubtog, fom bog egentligen cr en 0»erf«ttelfe<br />

paa arbfl, Ijuovtil ftben cr feict Sagrange'g lillisg. Zitelen<br />

l;erpatt cr:<br />

40


«., e;jit8 a«g Snlcrg Sllaetfa ton 3. 3. Sbcrt. 2 ai)cile,<br />

Gulcfg ocllflanbige 9lnldtnng jut Sllgcbra, 3ter Xlicil,<br />

»on Acnplcr.<br />

$. 24. 9Si ^nvc feet ovenfor (I. §. 116 og 118), at<br />

«n qvnbrntifT SCqvntion ^nr flebfe to Oplegninger; ligelebeg<br />

f ac vi (§. 15), ot SSqvntionen for y, ber vnr nf 4be ©rnb,<br />

i)avbe 4 Oplegninger. 3llminbcligvitg vil en^ver ?(5qvntion<br />

^nve fnnmnngc Oplegninger, ^vilfe falbcg Svebbcr, fom<br />

Crabcn ben cr af.<br />

^albe vi Opiegningernc p eg q, og fatte SGqvationcr.<br />

(I. §. 118) unber ben gorm<br />

x' -j- Ax — B = o,<br />

fan, ^vtg vi bcrmeb fammenltgne<br />

(x — p) (x — q) = x^ — (p 4- q) x 4-pq<br />

(,ibi'ccg, Ot bn<br />

p =: —iA-^YB^T^<br />

q=zz-iA-YB^iA^<br />

er<br />

p 4- q =1= — A<br />

pq = -B<br />

gelgcligcn, nnnr enten x == p cller x = q, cr<br />

(x — p) (x — q) = x' -j- Ax — B = o.<br />

SSi funne nitfno fremftillc be qvnbrntifFc ?(SqvntiDnct5<br />

Oplegning fom cn !9Jct^obe, f)vorveb vi oplefte et ^robuct<br />

of ben gorm x^-j-Ax — B i to gnctorer.<br />

Sigclebeg betrngte vt ferft ben rene cubifTc 3@qvntion:<br />

x' = a<br />

eller<br />

x' — a = o<br />

^vor vi ville ffftte a = p', fnn cr een Oplegning<br />

X = p.<br />

II. 8


114<br />

SBctrngte vt benne Opl0§ning, fom een, ber voc gonen<br />

Mb poo, ot finbe en goctor of bet cubiffe 'Probuct x» —p%<br />

bo vor benne x —p, og bivibereg x'—p^ meb x —p,<br />

Hev Clvoticnten x^-j-p^^ + P^^/'


115<br />

Jjovbeg cn Sffiqvntion nf 4be, stc ®rab JC, bo lob<br />

ben fig ligelebeg fammenligne meb et ^robuct of 4, 5 !C. goc;<br />

torer; og pao fomme 'DDJoobe vilbe fibfle Secb vffre ^robuc;<br />

tct of olle Slebbcrne, anbct Secbg €ocfficient ©ummen of<br />

olle Slebbcrnc tagne negative.<br />

§. 25. Sn^vcr fulbftffnbig 5@qvatton o: ^vori olle "Po;<br />

tcnfer of x, fro ben ^eiefte til ben lovefte, bcfinbcg, lober<br />

(tg omforme til en onben, i ^vilfen ben nffft.yiefle QJotcng<br />

fottcg.<br />

Ser Vffre og given f.^r- ben cubiffe 3@qvation<br />

X' +Ax=4-Bx-j-C = o<br />

foo, ^vig vi ffftte x 4- i A = y, cller x = y — | A,<br />

bo cr 2@qvationen<br />

y._Ay'-|-^A=y —^A''<br />

4-Ay^-iA'y -j-^ A^<br />

4-By-iAB(<br />

4-c)<br />

©ffttcg ^er nu<br />

B —iA^ = D, ^VA^—iAB4-C = E,<br />

fao cr ben ombonnebe 3@qvotion<br />

y3 4-Dy4-E = o<br />

Om 3©qvfltioncn ^ovbe Vffret of ^vilfenfom^dfl ®rob,<br />

^avbe vt Vffret iftonb til ot bc^onble ben poo fomme 5)Joobe,<br />

veb, noor ©roben vor m, ot ffftte<br />

X = y —^A<br />

SBi be^evebc blot ot gobtgjere, ot<br />

(x —isA)'" = X'" —Ax"-' .^<br />

nogct, fom fibcn ftrffngt bcvifeg; men for bet gerflc fan inb;<br />

fccg veb virfdigen nt op^eie (x ^ s A) til ben mte >Potfn«.


1x6<br />

§. 26. SJefinbcr pg i cn orbnct 3


117<br />

oltfao cr -j- 3 en 9Iob for SSqvotionen; ligelebeg ere 4-1<br />

og 4-2 Siebbcrne. ©oalebcg cre be olle funbne.<br />

jjavbe vi fom onbet Srempel ^avt<br />

X' —i3X"4-49x —45 = o<br />

foo ere for bet fibftc Secb, 45, SDJonlene i, 3, 5, 9, 15/ 4;;<br />

of biffe er iffun 5 en Slob. Se to nnbre Stebber ftnbe«<br />

«eb ot bivibcre meb x — 5<br />

x^ — 8 X -j- 9<br />

5 — 5) ^' ' — 13 X-<br />

_x' 5x^<br />

' +<br />

—<br />

+<br />

25i jTuflc oltfao oplefe ben ubfomne 2@q vntion:<br />

x=--8x<br />

:-^9 0<br />

X- — •8x<br />

8x'-<br />

8x=<br />

: z=<br />

4"<br />

4-49X. — 45<br />

+ 40X<br />

9x<br />

— 9x + 45<br />

— 9<br />

16<br />

(x-4)^ = 7<br />

X —4 = ±Y7<br />

X = 4 + ^7<br />

SSqvotioneng tre fUebbet ere oltfao<br />

5/ 44-^7/ 4 —V7<br />

©om trebie Srcmpel v«re given SSqvationen<br />

x'4" 2x^4-3 x-j-44 = o.<br />

?ageg 'DSaolene of 44, ncmlig i, 2, 4, 11, 22, 44,<br />

eg meb biffe gjercg gorfeg, fon vii ?


118<br />

•gotiv 3lob —4, Se to onbre finbeg of ben qvobratijTe<br />

3@qvntion, fottt opftnoer veb ot bivibcre meb x-j-4:<br />

X^ — 2X-|- II = O<br />

Serof ere 9l0bberne i -j- Y— 10, i — V—10<br />

§. 28. goc ot beftemme, ^vorvibt Subifroben lober<br />

fig ubbroge of et Ubtryf of ben germ A +V'B, lige meb<br />

bet, ^vorof ovenfor (§. 9) O.vabrotrobcn cr ubbrogen, ville<br />

vi bc^onble bet poo en lignenbe 9)toobe, fom bee er viifl.<br />

©fftte vi:<br />

V^A + v^B = X + Vy<br />

So er omvenbt<br />

A +VB = X'±3x^V^y4-3xy+ y/'y<br />

©ommcnltgneg ^ct be rotionole og irrnttonote Sele,<br />

foo cr:<br />

I) A = x'4-3xy II) V^B = (3x^4-y)V"y<br />

Cvobrercg begge 3®qvntioner, bo ct<br />

A* = x^-J-dx-y-j-gx'^y^<br />

B = 9x^y4-6x^y-4-y^<br />

A' —B = x« —3x^y 4-3x2 y^-y*<br />

= (x" —y)'<br />

Saber €ubtfroben (ig nu nete ubbroge of A^ — B, og<br />

bliver f. Sr. c, foo er<br />

x' —y = c<br />

3nbffftteg SCffrbien of y = x'^ — c^ ubbrogen of<br />

beitne 5(2qvotion i I), foo cr<br />

A = 4x^ — 3XC, cller ogfoo<br />

4x' — 3 ex — A = o,<br />

^vorof nu x lober (ig beftemme, ibet ben ncmlig bliver ratio;<br />

nnl, foofrcmt bet givne Ubtrpf vtrfelig fon mobtoge gormctt<br />

x± Vy") cr X funben, bo finbeg let y = x^ —c.


119<br />

g.Sr. -5^(7 4-5^2) = V"(7 4-V'5^)<br />

.^cr cr A= — B = — I, ^vorof (Subifrobcn er — i = e;<br />

nltfoo<br />

4x'4-3x —7 = o<br />

X^ 4"TX T = o<br />

©ffttcg z = 2x, foo er^olbeg<br />

iz' + iz —i = o<br />

z^-j- 3z — 14 = o<br />

^erof er ccn 9iob 2, oltfoo z = 2, x = i, y = x*<br />

— c = 2. gelgcligcn er Ubtn;ffet i-j-Va.<br />

Sill. 2}« ber (tebfe forfege om Subifroben lober ftg<br />

ubbroge of A^ —B. (Sr bette iffe 2ilffflbet, vil bet ofte<br />

Vffre muligt ot bringe benne ©terrdfe til et fulbfomment<br />

€ubiftal vcb ot multiplicere meb en vilfoorlig gnctor, f; ba<br />

cr, ^vig vi ffftte<br />

•Itfoo<br />

^vorof<br />

V(A^ —B)f = fm<br />

A' —B = f^m' ^ (x2_y)»<br />

x' — y = mf ^ z^ c<br />

4x' — 3mPx — A = o<br />

1<br />

ellcr, fffttcg X = uf^, foo er SSqvotioncii<br />

4fu' — 3mfx — A = o<br />

^vorof u fan finbeg, og bernf ntter x = f^u,<br />

fSin cr y = x^ — c = x' — mf ^ = u» f ^<br />

— mf^ = f* (u^ — m), oltfno<br />

Yj z= f T Yn'^ — m


120<br />

g.Sj;. f(8 4-4V^5)<br />

^er er A" —B = —16; for of gjarc benne ©terrdfe til<br />

et fulbfomment dubiftol, lober og multiplicere meb f = 4,<br />

fao cr fm = — 4, m = — I, og Seqvottoncn for u<br />

i6u3-j-i2u — 8 = o<br />

u-'4-TU—i<br />

= 0<br />

©ffttcg u = ^z, bo er<br />

J-z ^4-iz-i- = 0<br />

z '-|-3z —4 = 0<br />

.rjvorof z = I, u<br />

Vy<br />

3(ltfao ^ele Ubtri;ffct<br />

= ^v X = 1- V^4<br />

= V4Vi+T<br />

..^.-^ + V5<br />

Y2<br />

§. 29. Sigdcbeg, ^vtg vt ^ovbe ^ovt Y(,A±Y—B)<br />

= X + V— y, vnr<br />

A ± Y^—B = x' + 3x' V—7 — 3xy + y V ^<br />

Jjvornf<br />

I)A=x'-3xy II) V-Brr sx'V'-y-yV-y<br />

m\a«<br />

A^ = x« —6x*y4-9x'y2<br />

03<br />

+ B = T9^*y±6x-y'HFy^<br />

A^4-B == x« + 3x^y4-3x'y^4-y-<br />

= (x' + y)'<br />

95etegneg nu otter Cubifroben of A^ -j-^ "i«^ c, eller ffft;<br />

teg x' -|-y = c, f.^ a-<br />

y = c —X'<br />

i'-i ex 4-3:


i\l :'.'.n<br />

121<br />

-. ^-' — 3 f X — A —: o<br />

3lf benne X^v'ation labcr x fig l.jLuime, og fr.'nf<br />

«u>'r y = c — x-<br />

3ntfan<br />

g.Sr. ^"(9 4-25^^<br />

jjcr er A = 9<br />

B = 2 X 25- = 1250<br />

A^-J-B = 1331<br />

c = II<br />

4x3 —33X —9 = o.<br />

©attcg X = l-z, fnn cr<br />

•^ z' — V z — 9 — o<br />

z' — 33Z —18 = o<br />

Jjvorof cn 9vob er z =: 6, nitfnn x = 3, y = 2, og<br />

f;ele Ubtn;ffet bliver<br />

Z + Y~2<br />

Sill, ©civ om A^-J-B intet £u6tftal fidvh- vip;;.<br />

^ovbc vi bog funnel bringe bet bertil, veb ligcfo;. iiiijcu<br />

(§. 28 5ill.) ot multiplicere meb cn gactor f; b^ fatte v«<br />

.^vornf<br />

altfao<br />

V^(A» 4-6)7 = fra<br />

c = f*m<br />

4x' — sf^mx — A = o<br />

fffttcg nu x = f^u, fnn er<br />

4fii' — 3mfu — A o<br />

SRaor nu ^crof u er funben, fao cr<br />

X = Fu; Y^ = f^yiT^^i;


122<br />

g.S):.<br />

J?er et<br />

VC-9-V-175)<br />

A = -9<br />

B = 175<br />

A^ 4- B = 256<br />

Scttc er intet Subiftol; men fffttcg f = 2, foo ec<br />

Y512 = 8 = fm<br />

«Itfflfl m = 4, og 2@qvottone«<br />

8 u' — 24u-j-9 = o<br />

(©ffttcg z = 2u, foo er ben<br />

z' — i2z4-9 = o<br />

^vorof z = 3, u = i, oltfoo<br />

X = f V^2; Y^ = Vs X'<br />

ellec ^elc Ubtri;ffet ec<br />

Y2U-i^~7)=^'~<br />

Y4<br />

§. 30. SSi funne (tebfe bcftcmt eplafe en^vcc cubif!<br />

SiSgvotion poo felgenbe, nfSnrbnnug ferft bcvtfte ?Olaabc;<br />

gormlen, fom tjenec ^ectil, fooec eftec ^om IHovn of bett<br />

corboniffc.<br />

garft inbrctteg 2@qvationett fnnlebeg, nt berof x* ec<br />

borte (§, 25); bett er^olber oltfao felgenbe olminbeligc<br />

©fiffclfe:<br />

x'-j-px-j-q o<br />

?(ntoge vi nu, nt x = u-j-t, fno ec<br />

x' = u'4-3u=t4-3ut'4-t*<br />

= u- 4-1^ 4- 3 ut (II4-1)


123<br />

^vornf ntter fan bnnncg 2@qvntionen<br />

x' — 3 utx — (ll' -f-1') =r o<br />

©nmmcnltgncg bette Ubtri)f meb<br />

x'4-px4-q = o,<br />

bo er<br />

ut z=: —ip u'-j-t' = —q<br />

3tu Iflber u og t fig finbe ifelge §. 14. 9Si ^flve<br />

ncmlig<br />

« P^<br />

" 3t<br />

^vilfet inbfat giver<br />

—-^4-t' = ~q<br />

271'^ ^<br />

ts4-qt' = TVP'<br />

(^:q)' =:^q^<br />

(t'4-^q)2 =:iq-4-^p«<br />

t'4-iq= ±Viq=4-^7<br />

t^ = - i q + riq^4-j^p3<br />

U' ^ -^-q + Y'iq'^4-^Vp*<br />

SScb ot ubbroge Subifrobcn cr^olbcg u og t; 6e^olbe§<br />

blot bet evcrfle 2egn, foo cr<br />

X z:=z u-j-t =<br />

V'(- 4 q + Viq^+^p') + Y(r' H - ^i¥+^y<br />

©om Srempler vffre givne:<br />

I) X'—21 x-j-344 = O<br />

^er cr p == — 21; q = 344, oltfna<br />

iq'-|-^P' = 29241<br />

+ •\r29241 = + 171<br />

— jfj = —172<br />

X = VCI^ 4-^-343


Co'gcg "••-•? -•; to v.'ire Slebber veb nt bivibcre meb,<br />

x-f-8 pon • n forr;: .'.jle QKnnbe, ba cre biffe<br />

— 4 4-Y'—27, —4 — Y—27<br />

11) X'—6x — 40 = 0<br />

Sjet ex p = — 6, q = — .;o<br />

3fltfOfl<br />

Tq--f-^p' = 392<br />

+ Viq^TTvp = ± V392<br />

X = ^"(20 4- Y^) 4- f (20 — YJ^)<br />

2tnvenbe vl pnn lilfc cubiffe Stcotionol; ©t.errclfer gormlcit<br />

§. 29/ r«« cc<br />

A- — 400<br />

B = 392<br />

.Jjierof er Subifroben 2, oltfoo c =<br />

^qvntion er<br />

2, og ben ber funbne<br />

4x' — 6x — 20 =: o<br />

fom oplefl giver Sloben x = 2, nitfnn y = x* — e.<br />

r= 2, cQer vert Ubtrijf Inber fig foranbre til<br />

2 -j- V^2 -j- 2 — V^2<br />

•Itfoo cr 3\obcn for ben opgtvne ^©qvotion 4.<br />

Ill) X' — 12 X — 28 = O<br />

So er p = —12, q = —28, «Itfoo<br />

X = •\r(i4 4-r^)4-V"(r4-r:^)<br />

Jtnvenbe vi ^crpon gormlen §. 28, bn er beri<br />

A' — B = 196 — 132 = 64 = 4^<br />

gelgcligcn ^nve vi 2(Sqvnttoncn ber<br />

4x' — 12 X — 14 = o<br />

©ffttcg X = 4-z, foo er


^z' —6z— T4 = o<br />

T.' 13 Z 28 = O<br />

125<br />

?8i fomme fonlcbcg tilbngc pnn vor oprinbcligc 5GFqvo;<br />

tion, og unberfege vi benne, veb ot toge ^Dioolcne for 28,<br />

ncmlig i, 2, 4, 7, 14, 28/ bo finbeg, ot ingen of bcm op.<br />

lefcg, men ot altfnn 3ioben bliver irrntionnl. Sen bcftem;<br />

meg Icttcft veb Sognvit^mer<br />

log 132 == 2,12057<br />

logV^i32 = 1,06028,5<br />

+ 7^132 •=: + 11,489<br />

25,489<br />

2,511<br />

Ubbrngeg of biffe to ©terrelfcr ntter €ubifrobcn, fan et:<br />

log 25,489 1*40635 log 2,511 0,39985<br />

3) 3) - -"<br />

0,46878 0,1332s<br />

jjertil fvorer Sollcne<br />

2/94293<br />

n 1/35919<br />

Nltfoo i 4,30313<br />

14<br />

IV) x' —i2x'4-36x —7 = o<br />

Jjec mnn ferft nnbct Sceb bortflnffcg; fffttcg berfor<br />

(§. 25) X — 4 = y, fnn ^nveg<br />

y._j_i3y2-j_48y4- 64 = X'<br />

— i2y^ — 96y—192 = —i2x*<br />

36y4-i44 = 36X<br />

y" * —i2y-j- 9 = o


126<br />

S^ex er p = —12, q = 9, oltfoo<br />

V^iq'4-^P^ =<br />

g.elgeligen<br />

V^V ^ ^<br />

V^-175<br />

=<br />

y = vA-9 4-V^^i75 4- v/"-9-y"-i75<br />

2 2<br />

3fnvenbcg ^crpoo gormlen §. 29, foo inbfecg of bet (§. 29<br />

'5ill.) onferte S;;cmpd, ot<br />

2 2<br />

3tltfao<br />

X = y-j-4 = 7<br />

§. 31. (Snbnu er en egen 5)Ioabe ot opleife be cubiffe<br />

3(5qvotioncr poo, fom grunbcr (ig pon be trigonomettijie<br />

gunctionerg SRotur.<br />

?oge vi gormlen (Srig. §, 6 n.)<br />

cos (a 4" b) cos a cos b — »In a sin b<br />

og ffftte beri a = 2 b, foo er<br />

cos 3 b =<br />

men bo<br />

cos 2 b cos b — sin 2 b sin b<br />

cos 2 b = 2 cos b^ — I (Xrig. §. 9 XV)<br />

sin 2 b =<br />

foo cr<br />

2 sin b cos b CJrig. §. 9 XIV)<br />

cos 3 b = 2 cos b' — cos b — 2 sin b'^ cos b<br />

©ffttcg sin b^ = I — cos b^, foo ^ooeg<br />

cos 3 b ::= 4 cos b' — 3 cos b<br />

Jpvorof otter<br />

cos b-" — I- cos b — i cos 3 b o<br />

©ommenligncg bette Ubtn;f meb en cubifT ?@qvnti«it<br />

of ben gorm


eg beri fffttcg<br />

x' —px — q := O<br />

X =r= r cos b<br />

127<br />

q =: i r' cos 3 b<br />

foo bliver<br />

r' cos b' — -J r^ cos b — i r' cos 3 b = o<br />

3tf be to befjcnbte ©terrelfcr p, q lobe r eg cos 31*<br />

fig bcftcmme, ncmlig:<br />

r = V^p; C05 3b = -^-<br />

jjvornf bo otter fnn finbeg<br />

X ^^ r cos b.<br />

So cos 3 b = cos (360° 4" 3 !•) = •^os (720'<br />

-j- 3 b), fnn finbe ogfoo felgenbe 3@qvotioncr ©teb:<br />

r^ cos.(i20''4'l*)' —|r'cos(i20°4-b) —Tr'cos3b = o<br />

r' cos(240°4"^)^—Ir^ cos(240°-j-b)—•|-r'cos3b = o<br />

jpvorof inbfeeg, ot t bet jjde f)flveg, of be funbne SSfftbicc<br />

for r og cos 3 b, felgenbe 3 Slabber fee x<br />

X == r cos b<br />

X = rcos (i20°4-l')<br />

X =: r cos (240° -j- b)<br />

So cos 3 b (tebfe moo vffre minbre enb i, fan fan<br />

4q<br />

i<strong>ttu</strong>tt benne Opl0gningg;!DiOobe onvcnieg, noor -^ ex en<br />

egentlig SSref b. e. r' >4q, ellec<br />

r« > 16 q^<br />

(fp)'>i6q^<br />

t^P^>i6 q^<br />

^P'>4-1'


128<br />

.A^ct cr oltfna bet Silffflbe, ^vor ben corbonjTe gormel giver<br />

tn umulig ©t.errclfe; bo, ^vig man fommcnligncbc ?£>et\)bi<br />

r.ingen of p og q meb 93eti;bntngen of bem (§. 30)<br />

P = — P<br />

?i!tf'a<br />

q =<br />

T q T^ TT 1' 4 q TT P'<br />

b. c. cn negativ ©t^tcclu', l/^^ig Cvabrnt; 3{ob cr tmoginair.<br />

©om Grcmpd vix'ci giinn Gjremplct §. 30 IV, fom<br />

fornnbrct er<br />

y3 —i2y-j-9 = 0<br />

jjer er p = 12, q == —9<br />

3lltfnn<br />

r = V^ip = 4<br />

cos 3 b = — ^ == — .^%<br />

log cos 3 b = log — .j\ = 9,<br />

3b = 124° 13'42"<br />

b = 41 24 34<br />

120°-J-1* =^^^= 161 24 34<br />

240 4~^ = 281 24 34<br />

^•.•rnf cre £ofinufferne<br />

9,87506 9*9767- n<br />

log 4 = 0,60206 0,60206<br />

0,47712 o,57878n<br />

3,0000 —3-7913<br />

•' Itfaa SSffrbictne of x ere<br />

4-7/ 4-0'2087/ -|-4*7913<br />

."5012 a<br />

9 29627<br />

0,60206<br />

9*89833<br />

0,7913<br />

i^"'i onbet Srempel ville vi tnge SSqvotionetl<br />

X' — 18 X — II = o<br />

4 • tV p = 18, q = II, r r= "^^24


3tuvenbe vt nu til Svcgningen Sog.uit^mcr, fnn cr<br />

log 24 =nz 1,380211<br />

log V"24 :=. 0,690106 =: r<br />

]og4q = 1,643453<br />

log r^ = 2,070318<br />

log cos 3 b = 9'573i35<br />

3b = 68° i'24"4<br />

b =: 22 40 28, I<br />

i;o4-l> = 143 40 28, I<br />

240 4-b = 262 40 28, I<br />

log cos b =:= 9,965065<br />

logcos (i2o4-b) = 9,900478n<br />

log cos (240 4" 1>) = 9*10553411<br />

log r = 0,690106<br />

3fl£faa ere 3v0bbetne<br />

4- 4*52034<br />

— 3'89569'<br />

— 0,62466<br />

129<br />

21 nut. goruben be cutiffe ?ffq»ationcr, Orig fnlbfltsnbtge<br />

Oplegning cr l.xvt i 5- 30 eg 31, labe ^ggBationcrne<br />

af 4bc ®rab fig in^lafe oeb en HiictI;obe, cmtreiit liig ben<br />

cavbanffe gormel (5. 30). S-^sfexe «!gqrationer bcviraob<br />

labe fig iEfe ainitnbcligen cplsfe.<br />

9Jaar 9i»bbeviie eve rationale, oil man ofteft reb got:<br />

feg Ennne finbe biffe, og ber labe fig f^ere SKeglev gioe,<br />

Ipovoeb btiTe lettcg; ere be irrationale betimob, faa funne<br />

vi anociibe forfTjcllige ailn«rmelfeg=aJletI)ober. gnlbflKn:<br />

bigeve Unbervetning berom, enb I)cr fan gioeg, finbeg i<br />

be ubfovligeve iaxehtiet ooer QJlgebra, f." er, gnlevg anj<br />

f«rte 5S«rf (§. 23), og fccgubcn i<br />

Lacroix Eleinens d'Algcbre.<br />

§. 32. gortfnttcg en nritfimctijT fnmmcn^ffugenbc


130<br />

umtbbelbnrt foregooenbe govf)olbg eftcrlceb, fan bonnebe otte<br />

be forfFjcUige ©t.evrclfcr, fom fom inb i biffe gor^olb, eftec<br />

bereg Orben, en oritfymctifT iprogregfion.<br />

©onlcbeg bonne f. Sr. 5oIlenc i bereg noturlige Orbeit<br />

en QJrogregfion, bo<br />

I — 2 = 2 — 3 = 3 — 4 = 4 — 5 JC'<br />

Sigdcbeg ville i, 3, 5, 7 cller olle ultge tal bonne<br />

en oritl)mctiff


ftnnc unbernebcn, nngive Sebbctg ^piobg i sprogrcgfioncn, og<br />

folbeg SSiferc (Indices).<br />

laqe vi et Secb, ^vig SSifer vi ville betegne meb n,<br />

lob bet fig beftemme veb folgcnbe Ubtn;f<br />

a4-(u — i)d<br />

Sctte Secb ville vi fnlbc bet nlminbdige Secb, og be;<br />

tcgne meb t; fnttcg ncmlig n = i, = 2, = 3, := 4 - _<br />

fan vilbe bcvveb nlle Scbbene i 'Progregftonen efter Orbnen<br />

fremfomme.<br />

$. 34. ©egte vi ©ummen of aUc Sebbene i en fnn;<br />

bnn nrit^mcttfT


132<br />

Sni. Snbffftteg i bette Ubtri;f cftcrfinnnbcn n = i,<br />

n = 2, n = 3 ;c., foo cr^olbcg: bet ferfte Secb, ©um;<br />

men nf be to ferfte, of be tre ferfte e. f v. Sctte ^ar gi;<br />

vet 2tnlebning til nt fnlbe Ubtri;ffet ^rogrcgfioncng fumnin;<br />

toriffe Sceb, cftcrfom bet ubtri;ffer olmtttbdigcn ©ummen<br />

of olle Secb fro bet ferfte til bet nte ellcr olmiubclige<br />

inclusive.<br />

§• 35' 3 be ubviflcbe Ubtn;f<br />

t = a4-(n—i)d<br />

s = A n (a -f-1)<br />

finbeg 5 focffjetlige ©terrelfcr: a, d, n, t, s. So »i<br />

^avc to 5@qvationer, funne to ©tevreif'er anfceg fom ube;<br />

fjenbte; cller, noor tre ere givne, lobe be evrige fig be,<br />

(temme; fonlcbcg opftnne 20 forffjcllige Opgnver, fom olle<br />

ere opbfte i felgenbe 5;abel<br />

1) a, d, n<br />

2) a, d, s<br />

3) a, n, s<br />

4) d, n, s<br />

5) a, d, u<br />

6) a, d, t<br />

7) a, n, t<br />

8) d, n, t<br />

t<br />

s<br />

t = a4-(u —i)d<br />

t = — 1- d + Y'2 ds 4- (a — Vd)-<br />

2S<br />

n<br />

u 2<br />

s =: \- n (2 a -j- (11 — i) d)<br />

a-f-t , (t4-a)(t —a)<br />

''"= 2 + 2d<br />

s = J.n(a4-t)<br />

s = 4-ii(2t —(n —i)d)


9) a, n, t<br />

lo) a, n, s<br />

li) a, t, s<br />

12) u, t, s<br />

13) a, d, t<br />

14) a, d, s<br />

15) a, t, s<br />

16) d, t, s<br />

17) d, n, t<br />

18) d, n, s<br />

19) d, t, s<br />

20) n, t, s<br />

n<br />

a<br />

d<br />

t —.«<br />

n — I<br />

2 s — 2 an<br />

u (n — i)<br />

(t4-a)(t- -a)<br />

2 S — t — a<br />

2 nt — 2 s<br />

n (n — i)<br />

t —a<br />

n = i4-<br />

133<br />

d —2a ^28 /'2a—d\s<br />

~~ 2d<br />

-NT + V^-^dV<br />

2S<br />

a-j-t<br />

2t4-d r/^2t-|-d\-_2s<br />

7d~~ - \ \J~^d~J ~~d<br />

a = t — (n — i) d<br />

s (n — i) d<br />

n 2<br />

a == ^ d + Y(t-j-h d)'' — 2 ds<br />

2S<br />

n<br />

?ilffflbcne: a, d, s|t; a, d, s[n; d, t, s[n; d, t, s|a<br />

opiefcg vcb qvnbrntiffe 3i@qvnttoncr; begnnrfng finbeg bet bob;<br />

bclte 2cgn og Omftffnbig^cbcrne maae ofgjere, ^vilfcn Op;<br />

legning ber togeg.<br />

21 n m. ©om erempler paa Slnrcnbctfen af biffe gormler<br />

»«re gione:<br />

i) S?Mb et ©ummen af be ti fwfle %al, ellcr i,<br />

2, 3 -----IQ,


134<br />

.^er er a = i* t = lo, n =: lo; oltfna<br />

s z=L ^-n (a-j-t) = 55.<br />

2) (Sen, brig ©age fra SBcgnnbelfen nf var 100<br />

Oibblr., erl)0lbcr ?lar for aiar flebfe 20 Slibblr. Sillag,<br />

Ijror flor er ba bang ©age i bet iite Slar, og Ijoormc;<br />

get l)ar l)an oppebaaret i alle biffe 3lar?<br />

.^er er a = 100, d = 20, n = 11, flltfrto<br />

I = a4-(n—i)d zzn: 300 OiOblr.<br />

s z=z (2 a 4- (n — i) d) ~ = 2200 3ibblr.<br />

2<br />

3) 2>cr er og given cn sprogregfion, I;oig ferfte Sceb<br />

cr 13, ©iffercntg cr —2, ©umma cr 40.<br />

J?ec cr a = 13, d ^ —2, s = 40, altfaa<br />

(a —id)^ = 14^ = 196<br />

2ds = — 160<br />

V^2ds4-(a —-id)- = V^36 = ±6<br />

Slltfao<br />

t=i±6=j_^^<br />

gor n(«tmere at beftemme $R(sEfen, villc vt tilmeb af<br />

famme givne ©terrclfe f^ge n. 3)a cr<br />

/'2 a —d\2<br />

2S , f2TL — d\*<br />

2S<br />

-j- = -40<br />

"d+v-^d-J) = ^<br />

llW)rageg Ocraf 9ioben, ba er benne i 3*<br />

5lltfao<br />

9ioben, b<br />

• 10<br />

4<br />

Sagcg oltfao n = for t 7±3 ben forfle 93a!rbie 7, fao footer ^cr:<br />

til n := 4, 03 SiojEEen cr<br />

13* II' 9« 7«<br />

aageg berimob for i ben onben SStsrbic —5, ba er<br />

M = 10, og OioeEEcn<br />

13* 11/ 9' 7' 5* 3/ i» —If —3/ —5»


135<br />

SSegge 3i0!tfcrg ©nmiua cr 40, eg faalebeg cr bet<br />

olbdcg nbeftemt, l^oilfen oi finllc tage.<br />

§. 36. SBctrogtc vi bet fummatorifTc Sceb af ben axitl)t<br />

metiffc 'Progregfion<br />

s z=^ Vn(2a-j-(n — 1) d)<br />

fom nlminbeligt Secb i cn Slffffc, bn blcv benne, ^vig n fnt;<br />

teg efterl)nnubcn = o, = i, = 2, = 3<br />

o, a, 2a-j-d, 3a4-3d, 4a4-6d, -|<br />

of ^vilfcn Dvffffe vi funne toge Sifferentfcrne, fom bleve<br />

a, a-j-d, a4-2d, a-j-3d<br />

SSi f)a\>be faalebeg of ben ferfte SSffffe en Slffffe of Siffe;<br />

rentfer, fom blev en orit^metifT ^rogrcgfion, ^vig Sifferentg<br />

blcv ben beftanbige ©terrdfe d.<br />

©dv om til olle Sebbene i SIffffen vnr feict cn com<br />

ftnnt ©terrclfe b, bleve Sifferentfcrne bog be fnmme, ellcr<br />

fnmme Sifferentg; iKffffc fremfom; vi ville begnnrfng give<br />

3iffffeng nlminbdige Sceb ben germ<br />

b-j-4n(2a4-(n—i)d)<br />

og felve Slffffcn er^olber ligelebeg ben nlminbdige gorm<br />

b, a-j-b, 2a4-b-j-d, 3a4-b-j-3d,<br />

ncmlig for SSffrbierne n = o, n =z i, n = 2, n = 3--<br />

men ville vi, ot n, fom fovf)en, ffol beti;bc SSiferen, fno nt<br />

benne for bet ferfte Sceb bliver i, for bet nnbct 2 !C., fno<br />

mootte bet i gormlen for bet olminbdige Sceb fig befinbenbe'<br />

n foranbreg til n —i, foo ot bet olminbdige Sceb bliver<br />

b4-^(n —i)(2a4-(n-2)d)<br />

Sn foobon Siffffe, fom ben fremfatte, folbeg cn orit^;<br />

tncttfF atffffe of on bett Orben, ligefom ben fffbvonligt<br />

fltit^mctijTe ^rogregfton fnlbcg nf ferfte Orben.


136<br />

§. 37* ©Wteg b = o, ^vorveb ba bet ferfte Secb<br />

forfvinber og n bel)olber fin ferfle 55eti;bning (§. 36), faa<br />

opftooer en ortt^mctifT SIffffe nf nnben Orben nf felgenbe<br />

gorm<br />

a, 2a-f-d, 3a4-3d, 4a4-6d<br />

©jereg f;er nu a = i, fan er for d =. i Stffffert<br />

n (n 4- i)<br />

J, 3, 6, 10<br />

2<br />

for d = 2<br />

I, 4, 9, 16 n*<br />

for d = 3<br />

n(3n —i)<br />

I, 5/ 12/ 22 —<br />

2<br />

for d = 4<br />

I, 6, 15, 28 n(2n —i)<br />

0. f V.<br />

25etrngteg biffe Slffffer neiere, fno Inber, nnnr Snllcne btt<br />

tegneg meb ^uncter, ben ferfte Slffffc for d = i ftg<br />

fnnlebeg frcmftille<br />

ie fnne begnnrfng 3?nvn of '5 r t g 0 n 01; 5:01.<br />

Sen onben Svffffe for d = 2 bliver<br />

* f * * t • • • * • • • •<br />

Jiffc fnlbcg 0,vobrogonfll;'5ollcnc.<br />

©aalebeg fcembelcg falbcg nlle %al, fom cre bnnnebe<br />

pno fnmme ^DJnobe, ncmlig for b = o, a = i, og d<br />

ligcftor meb et f)edt 5al, ^oli;gonfll; 5oI.


137<br />

Set bliver let nt beftemme 'Polt;gonn!;5nllcncg niminb'e;<br />

liac Secb. Sab m vffve ©ibe;^allct i ben *Poli;gon, ber vcb<br />

ct 'Polt;gonnl;'5al fTal frcmftilleg, fnn er d = m — 2. ^nbi<br />

fntica benne SSffvbie i goviulen<br />

s = ! n [j a 4- (u — i) d]<br />

livornf *Poliigoit;'5nllene veb nt faitc a = i cre opftanebe,<br />

fna ^nveg<br />

s = ! II [2 a -j- (n — i) (m — 2)]<br />

(m — 2) n- — (m — 4) n<br />

2<br />

fom cr 'PoIt;gonal;2nllcneg nlminbdige Sceb.<br />

3nbffftteg i benne gormel m = 3, fnn ^nvcg for<br />

Svigonnl; 'Jnllcne<br />

n' -j-11 n (n-j- i)<br />

2 2<br />

for O.vnbrngonal; 5:allenc<br />

n^<br />

for pentagonal; 'Jallene<br />

3"'—" n(3n — i)<br />

2 2<br />

for .^eragonnl;'Jnllcne<br />

4n^ — 2n z= 2n'—n = 2n(n — i)<br />

2<br />

0. f V.<br />

n fnner t 3llminbelig^eb 3tnvn of ©iben i Q3olt;gonal;<br />

Sollct. ©aalebeg ftgcg f. Sy. 3 ot vffre ©ibcn c 'pentago;<br />

nnl;5:nllct 12.<br />

§. 38. ©egte vi ©ummen of alle 'Poli;gonol;'5allene,<br />

fao inbfee vi let, ot olminbcligt bet ferfte *Poli;gonnl; 2nl er


138<br />

Set onbet<br />

Set treble<br />

(m — 2) i' — (m — 4) I<br />

(m — •2)2''<br />

(m- •2)3'<br />

2<br />

2<br />

2<br />

• ( m - -4)2<br />

• ( m -<br />

-4)3<br />

oltfno ©ummen of olle polygonal ;5nl inbtil bet nte<br />

(m-2)(i' + 2'-|-3----u--)-(m-4)(i-j-2-j-3 —n)<br />

Slier betegne vi meb<br />

2<br />

/n' og/n<br />

©ummen of olle 0-vabrat;'5ol fro 1 til n^ og ©ummen of<br />

olle noturlige ^ol fro i til n, foo et 'poli;gonol; •^oUcncg<br />

©umnio<br />

m — 2„ m — 4„<br />

2 •' 2 •'<br />

SSi ^ove nltfoo blot ot fege /n og /n-.<br />

Ubvifle vi vcb Jjjfflp of 2?tnomial;gormlen (a-j-b)'<br />

felgcBbe O,vobroter<br />

i^ = I<br />

2- = 14-2. i-j-i^<br />

3'^ = I 4-2. 2-j-2'^<br />

4' = I-F2. 34-3-<br />

n' == I -j- 2 (n — 1) -f- (n — 1)'<br />

(n4-i)^ = i4-2n4-n»<br />

eg obbereg biffe, foo ^nveg<br />

/(n 4- i)^ == n 4- I 4- 2/n 4-/11^<br />

eller


./(n -j- 1)=^ -/n^ = n + I 4- 2/n<br />

139<br />

©'errdfcn fornn Sig^cbg;5egn cv ©ummen of olle O.va;<br />

bvatev fro 1 til (n-j-i)S minbre enb ©ummen of nlle<br />

0.vabvatcr fra i til n^ D: cue (n-j-i)', nltfao<br />

(n4-i)^ = n4-i-j-2/n<br />

Jjvoraf<br />

/ll _ (n-i-iy-("-fO __ n(n4-i)<br />

J 2 2<br />

Si^ckbcg, ^vtg vt ubvifle Su&cvne, bo cr<br />

2^=i4-3« i-f3« 1^4-1*<br />

3' = 1-J-3. 24-3. 2--i-2'<br />

4' = I-I-3- 3-1-3- 3'-1-3'<br />

n' = I -I- 3 (n — 0 -I- 3 (n — i)' -h (n — i)*<br />

(n-j-i)' = i4-3n4-3n»-j-n^<br />

3tbbcvcg biffe, foo cr<br />

/(n 4- i)^ = (n 4- I) 4- 3/n 4- 3/n^ 4-/n'<br />

ijvoraf<br />

/(n 4- I)' -/n^ = (n 4- I) 4- 3/n 4- 3/n*<br />

0: (n -^- I)' = (n 4- I) 4- 3/n 4- 3/n^<br />

Ttltfao<br />

/n^= A<br />

(n4-i)3—(n-f-i) n(n-^I><br />

3 2<br />

(n -j- i)(n'-j-2n) n (n -j- i)<br />

^3 2<br />

(n4-i)(2n'4-n) n(n4-i)(2n4-i)<br />

2. 3 2. 3


140<br />

2(nvenbcg nu biffe gctmler for fa." eg fn til at finbe<br />

^oli;genal;'5allcncg ©um, fan cr benne<br />

m — 2 n(n4-i) (2n4"i) "^ — 4 n("-|-i)<br />

X X •<br />

2 2. 3 2 2<br />

Sen Ocftaaer nltfan of to Sele; cen nfi}ffngig of m, cn an;<br />

ben, f)vor m iffe forefommer, eller er liig<br />

/^n (n 4- i) (2n4-i) _ n (n -\- i)"N<br />

V 2. 2. 3 2. 2 J<br />

__ ^n(n+i)(2U-f 0 _ 2n(n4-i)\<br />

V 2. 3 2 y<br />

n (n 4- l) (n — i) n(n-|-i)(2n —5)<br />

2. 3 2. 3<br />

©oolebeg bliver bet fummotorifPc Sceb for ^rigonol;<br />

5:otlcne<br />

n (n -h i) (n — i) ^ nOH" i) (2 n — 5}<br />

X 3<br />

2. 3 2. 3<br />

n (n -t- i) (n 4- 2)<br />

2. 3<br />

for O.vobrogonal; 5otlene cller 0.vabrat;Sollene<br />

ii(n-}-i)(2n-j-i)<br />

2- 3<br />

fom vi f)nvc funbet ovenfor, ncmlig ^n*<br />

for ^cntngonol; 2^ollcne<br />

n- (n 4- i)<br />

2<br />

for Jpcrogonol; Sotlcne<br />

P(n4-i)(4"—i)<br />

2- 3<br />

0. f V.


141<br />

§. ",q. I53etrn9te vi bet fummntorifFe Sceb nf *poli;go;<br />

nnl;'5ai;u.o attov fcm niminbdigt Sceb for cn ni;e SJtffffe,<br />

far. opflcb nf ^vigonnl-'Snllene<br />

felgenbe SIffffe<br />

I, 3, 6, 10, 15<br />

of O-vabv.iijcnal; "Sallcne<br />

Kffffen<br />

I, 4, 10, 20, 35<br />

I, 4, 9, 16, 25<br />

1/ 5' 14/ 30/ 55<br />

of 'Pentagonal ;5a![one<br />

SIffffen<br />

I, 5, 12, 22, 35<br />

I, 6, 18, 40/ 75<br />

0. f. V.<br />

gvcmftillebc vi Sen^ebcrne i biffe Zal meb bugler, ba<br />

lobe be fig opflable i 'Pi;ramiber; faalebeg vilbe af ben fev;<br />

fte SIffffe trefibebe 'P>t;rnmibcr labe ftg opftnble, nf ben nu;<br />

ben prefibebe e.f v., begnnrfng falbcg bif\e Zc.l "Pijrnmi;<br />

b n I; 5 n I.<br />

Q3i;rnmibnl;'5nllenc ubgjere en nrit^metiff Slffffe nf<br />

treble Orben, vi funne nf bem ntter bgnne cn SJlffffc af<br />

fjevbe Orben 0. f v.<br />

3tlle biffe Zal, bnnnebe pnn ovenftnaenbc 9?inabe, fal­<br />

bcg figurlige Zal, jTjenbt SScnffvnelfen bog iffun meb<br />

Sicttc tilfommcr 'Poli;gonal; og ^i)rflmibnl;'5;nllene.<br />

§. 40. Sigefom ben fortfntte fnmmen^ffngenbe ntit^;<br />

metifFe proportion giver ben nrit^metiffe ^rogrcgfion, fnnle;<br />

beg giver og cn fortfnt gcomctriff proportion en geomctriff<br />

^vogregfion (I. §, 122). (£r en fanbnn "Pvogregfton given


J 42<br />

a, b, c, d, f t<br />

I 2 3 4 5 n<br />

^vor ntter 'Snllenc unbernebcn cre SS i f e r n e og t bef a 1;<br />

minbclige Seeb, foo vibe vi, ot felgenbe gor^olb finbe<br />

©teb: a: b = b : c = c: d = d: f. 3(ntogeg gp<br />

ponenten i biffe gor^olb nt vare m, fno ec<br />

a :z=z b m.<br />

b = c m<br />

c = d m<br />

0. f V.<br />

ijvorof felgcr<br />

a<br />

ni<br />

b<br />

m<br />

a<br />

2 m<br />

ni m^<br />

0. f. V.<br />

Siffe Ubtryf cr^olbe imiblertib en ffmplerc ©fiffclfe,<br />

peb ot ffftte<br />

bo cc<br />

I<br />

m<br />

b = ae<br />

c = ae*<br />

d ~—: ae'<br />

0. \. V.<br />

e fnlbcg t 3flminbeligl)eb 'Pcogregftoneng Sjtrponent,<br />

eg vi funne nu veb .fjjfflp of ben, bet ferfte Secb og aSif»t<br />

ren ubtri;ffe bet olminbdige Secb, cller<br />

t = ac»-»


143<br />

31 nm. etponcntcn forcEomincv faalebeg I)cr i cn mobfat<br />

q3eti>bning afbcn, l)oori bet cr brngt veb be geonietri=<br />

ffe sprevortioner (I. §. 78), ba bet ber ubtroEicr ben<br />

©terrdfe, l)worincb bet fovegaacnbe £eeb tnnltiplicercg<br />

ft>r at frembringe bet cftcvfi'Igcnbe. berfor Ijaue enfelte<br />

govfattevc fin'anJvct Cvponcnteng 2?et«bning oeb gorljoU<br />

bene, eg falbct (Jvponent ogfaa ber ben ©terrdfe, brov:<br />

nicb gorlebbet fTal inultiplicereg for at frembringe efter=<br />

lebbt't, bog bette ftribev albcleg mob ben alminbelige ©EtE<br />

og IH'ug, foiu obcvnievc finbeg bjctulet beroeb, at man<br />

t)ax M'ugt T't»ifiong:2cgnet : til at ubtroEEe ict geome=<br />

trifle gDvI)olb.<br />

§. 41. ©ege vi ©ummen s of ben geomctriffe 'Pro;<br />

grcofion, foo cr<br />

s zzzz a -}-ae-j-ae= -j |-ae"—^ -j-ae""'<br />

Sltultipliccveg meb e, bo er<br />

es = ae -j- ae^ -j- ae^ -j ae"— • -j- ae"<br />

©ubtro^creg evevfte Sinie fvn ncberflc, fno er<br />

ellcr<br />

es — s =: ae" — a<br />

altfnn<br />

s (e — i) = a (e" — i)<br />

e" — I<br />

e— I<br />

lif biffe to Ubtri;f for bet nlminbdige Secb t (§. 40)<br />

og for bet fummntovifTe s, lobe fig nu ligefom fov^en (§. 35)<br />

en 5nbel forfottc, ber inbe^olbt olle Oplegninger, nnnr tre<br />

of ©terrelfernc a, e, n, t, s vare givne, bn nt finbe cn<br />

fjcrbe; imiblertib vilbe vi bcelg ^er ^i;ppigt trffffc pnn ^eiere<br />

2©qvationcr, bcelg poo Srponential


144<br />

bette faalebeg frcmbelcg tiltagcr, ^vor flcsrf er ajefolfs<br />

ningcn cfter loo 2farg gorlob. S^ex er<br />

a looooo, e = -|i, n = loo,<br />

beraf fogeg<br />

t = ae"—'<br />

= 100000 (;i-i)<br />

Slnvenbcg til Ubtn>EEetg ajcvegning Sogaritl^mcr, ba et<br />

log 51 = 1,7075702<br />

log 50 =z 1,6989700<br />

log-ii = 0,0086002<br />

100<br />

0,8600200<br />

log looooo — 5,0000000<br />

logt = 5,8600200<br />

t ==: 724469<br />

2) Smcllcm I eg 3 ffal inbf«ttcg 10 ieeb, faa at<br />

Ijele Jprogvegfionen Eommer til at bcflaae nf 12 Secb;<br />

l;vab cv ba grponentcn ?<br />

a '<br />

t :z::z<br />

0 ^3^3<br />

11<br />

Y3 =<br />

I*<br />

ae"<br />

e>><br />

n =: 12,<br />

— 1<br />

t =<br />

= e<br />

©egeg • benne oeb 2ogaritl;incv, faa er<br />

lo §3 = 0,4771 213<br />

II)<br />

0,0433747<br />

e = 1,1050.32<br />

®a c nu er funben, labcr OireEfcn fig banne.<br />

3) €en l;ar inbfat i l.'otterict, ia Ijan I'lVnmbtc it<br />

fpille, 4 ©Eilf., eg, ba [)an tabtc, fat IcMu'lt nceftc<br />

©ang, eller 8 ©fill., 3bie ©ang attcr bobbcit, diet<br />

1 9JIE., og freinbcU'ci bobbelt; l)an beflager, at l)an<br />

til beni'.e ^vKEning ci tan gjevc bet ©ammc, ba til<br />

benne 3iibf'ttfni ril bclsbe fig til 682 3ibblr. 4 S)tf.<br />

9cn U'cvgeg; I)»ig I;an inbfoitter t'iiTe sponge og tabor, i<br />

I)oormange S;ri):fningcr tiar l;an fpili.'t, eg Dvormcgct Ijiif<br />

J;an i 3llt tabt ?<br />

3


^cr fegcg<br />

t<br />

logt<br />

=<br />

u<br />

t =<br />

a<br />

68<br />

n, »i Ijaue<br />

ae"—'<br />

log a-f-(ll —<br />

log t — log a<br />

log c<br />

2 Oibblr. 4 m.<br />

4, e = 2<br />

1) log e<br />

1 T<br />

1 I<br />

logt = 4,816480<br />

log a izzr 0,602060<br />

= 65, 65536 ©f.<br />

145<br />

4,214420<br />

Sioibcrcg bette nicb logo = 0,301030, ia crljolbcg<br />

14, altfaa<br />

n = 144-1 = 15.<br />

gor bet anbct ffulbe vi fege s; onti-n fan ben finbeg<br />

of 'Sonnlcn oeb .f^jffllv af bet nu funbne n, ctler ot oille<br />

let Ennne faac s a'f;cmt, uaf!;«ngigt af n. S&i Ijavi<br />

e" — I et — a<br />

e — I e — I<br />

•Slltfaa er l»er<br />

s = 2 X 65536 — 4 == 131068<br />

= 1365 Oibblr. I SRL 12 ©f.<br />

$. 42. 2if


146<br />

men, bo en^vcr egentlig ^xeU ^siexe ^otcnfer cre minbre<br />

enb be lovcre (I. §. 68), foo vil en egentlig .QJref, op^.eict<br />

til 'Potenfen 00, blive minbre enb ^ver ongivelig ©t.errelfc<br />

ellcr blive o, nltfoo er<br />

b<br />

— I<br />

1<br />

c<br />

ac<br />

c —b<br />

eller foranbre vt 'Jegnct til bet mebfotte i 9?ffvneren, bliver<br />

fem faolebeg blcv ©ummen nf Stffffett<br />

ab ab^ ab^<br />

a-l \ 1<br />

~ c ^ c^ ~ c^ ~<br />

©ffttcg ac == f, fan fif Svffffcn felgenbe ©fiffclfe:<br />

f fb fb^ fb^<br />

c ~c= ~ c^ ~ c* ~<br />

Set vnr juft ben gorm, vi fom til (I. §. 65 5ill. 2) vci<br />

Ubviflingen of SBogftnvbrDfcn, nf bcu gorm<br />

f<br />

3(fvc)det»e Sebbenc i Siffffen, fon lob ben fig enten 6c;<br />

trngte fom Siffcrentfen mellem to geomctrifTc 'Progregfioncr,<br />

^vilfe ba lobe fig fummcre fffrfFilbt, eller og funbe S);ponem<br />

ten bn-i fcctrngreg fom negativ. So blev ©ummen<br />

— a ac<br />

_b^_ " b4-c<br />

c


©ntte vi otter ^er ac = f, fnn vnr<br />

147<br />

i74-c c "^ c- c^ "*" c* '<br />

Set omvcnttc Ijcrnf er nllevebe ovenfor viifl (I. §. 65 5111. 2).<br />

21 nm. gov at anrenbe biffe gormler for ©ummen af<br />

uenbdige OiceEEcr, labcr og funiineve DiOjEEcn<br />

1 , 1 , 1 , 1<br />

l^er cr a = }, b z= 1, c = 3, altfaa ac z= i,<br />

c — b ^= 2, og folgcligcn<br />

s i<br />

S ^<br />

OitsEfen fremfommer ogfaa veb at f«tte<br />

1^ 1<br />

•2 3 — 1<br />

£abcr og fummcre SKoeEEcn<br />

I — T 4- ITS" ~ TTT H 1<br />

Sa er a := i, b = i, c = 5, altfaa cr<br />

5 _5<br />

5 + 1 6<br />

I;»oraf WtsEEcn cgfaa attcr tan fvembringeg.<br />

931 I;aobe ogfaa fnnnet fummcre ben cfter ben f#v(le<br />

gormel oeb at fcette ben liig<br />

-a+-xi^+TiW+—)<br />

gor ben ferfle Sect var<br />

a = I, b = I, c = 25, altfaa<br />

for ben anben S>ecl berimob rar<br />

a = ^, b = I, c = 25, aU{M<br />

gelgcligcn cr Ijcle atceEfen govfTjelleR mdlcm biffe ©ummer<br />

^0 r,<br />

•Zi o'<br />

§. 43. Sigefom vi faalebeg ollcrcbc ^avbe 'Pv^ve pao<br />

cct ©Ingg Stffffcr, ber lebe fort i bet Uenbdige, og font<br />

^avbc felgenbe ©fiffclfe<br />

10*


148<br />

a, ax, ax^, ax^, ax'<br />

^vor vi meb x betegnebe ben geometciffe Stffffcg (5j:poiicnt,<br />

foalcbcg funne vi ^ove mnnge onbre, ^vor bog be forfTjellige<br />

Soefficienter of x'g spotenfer ci vor ben fnmme, men fom<br />

^nvbe felgenbe ©fiffclfe<br />

a, bx, cx^, dx^, ex*<br />

jjnr i cn fnnbnn Slffffe Seefficienterne a,b, c,d,e<br />

(a fnn og onfeeg nt vffre €oeffi«ent, ncmlig for x'' = i)<br />

beftcmte og enbeligc 25ffrbier, fno inbfecg, ot vi ftebfe funuc<br />

give X, fom vi outage ot Vffre feronbcrltg, foo liben cn SSffc;<br />

bie, nonr vi ffftte ben liig en liben ffgte Sref, ot, ibet beng<br />

^0ierc


149<br />

ter ere ligeftore, i)Vab SOffrbier vi enb give x, fnn Inbcr bet<br />

fig bcvifc, ot a = A, b = B, c = C o. f V., eOcr<br />

ot famme ^otenfer of x ^nve i beggc ?i(rffcr ligeftore QLocffi;<br />

cicutcr. ''<br />

Sn<br />

a -j- bx 4- ex- -j = A -j- Bx -|- Cx= -j •<br />

for cnl)ver 23ffrbie of x, nltfan og for x =z o, fnn, ^vig<br />

bette inbfffttcg, forfvinbe beggc Siffffcvne, pan a og A uffr;<br />

nltfao<br />

a =1 A<br />

Jjevaf felgcr ba nu, ot for ct^vcit x cr<br />

bx-j-cx'-j-dx^-j = Bx-j-Cx=-j-Dx^4<br />

eller veb at bivibcre meb x, ot<br />

b 4- ex 4- dx' -j =: B -j- Cx 4- Dx= -j<br />

3tu finbe vi otter, veb ot ffftte x = o,<br />

b = B<br />

og fnnlebeg er og frembdeg c = C, d == D, cller fnmme<br />

^>ctcnfer nf x ^nvc i beggc 3lffffcr ligeflorc Socfficienter.<br />

Sfnvcnbdfen of benne ©fftning fnlbcg be ubcftemte Socf;<br />

ficicnterg 5)Jet^obe.<br />

§. 45. 3tf olle 3lffffer er ben vigtigfte og ben ^i;ppigfl<br />

anvenbcligc ben, ber fremfommer xieb Ubviflingen nf ct 5£>i;<br />

nomiumg


150<br />

Me biffe Ubtrijf funne frcmftilleg vcb felgcn&c gormel<br />

(a4-b)" =<br />

ai4--a"-'b-f-" a"-'b-4-<br />

' I 1. 2<br />

n(n-i)(n-^^_3^ _<br />

I. 2. 3<br />

vcb ncmlig ot ffftte cftcr^nanbcn<br />

Set er let ot overfee ben alminbelige Sov, biffe Secb<br />

felgc; betcgner ncmlig p SSiferen for et olminbcligt Sceb,<br />

fno er bette<br />

n(n-i)(n-2)—-(n-(p-2))_^^_^^_,^^^_^<br />

I. 2. 3 (p —i)<br />

Set umibbclbor foregooenbe Sceb er<br />

n (n — i) (n — 2)<br />

1. 2. 3<br />

(n — (p — 3))<br />

an—Cp —s)bp—'<br />

(p—2)<br />

a^ctegneg bette meb N og bet pbe Sceb meb P, foo er<br />

p— I a<br />

©fjenbt vi for be ferfte ^otenfer funne overbcvife eg<br />

om benne Sovg 9ligtig^eb vcb 3»buction, ibet vi virfc;<br />

ligen ubviflcbe, foruben ovennnferte, ogfno ben 6te, 7be.,,<br />

^oteng of a-j-b/ fna ««c Seven bog ferft beviift, noor vi<br />

gobtgjortc, ot, foofrcmt ben gjfflttc for een ^oteng, ben bo<br />

ogfoo gjfflbcr for ben felgenbe.<br />

SSi ville oltfoo outage gormlen gjfflbcnbe for ben nte<br />

^oteng, og bcrnffft bevife, ot, cr bette ^ilffflbet, vil bcii<br />

egfoo gjfflbe for ben (n 4- i)te ^etcng.


+<br />

I<br />

fO<br />

ID<br />

I<br />

13<br />

II II II<br />

1 ^<br />

to<br />

v.*<br />

I I<br />

I I<br />

I I<br />

I I<br />

tr' 1<br />

ty<br />

+<br />

4-<br />

i_<br />

+<br />

I ;<br />

+<br />

H I »<br />

I<br />

I<br />

I<br />

+<br />

O + +<br />

+<br />

ty<br />

+<br />

1<br />

•f<br />

ty<br />

+ +<br />

I<br />

-I-<br />

+<br />

I<br />

I<br />

I<br />

151<br />

S<br />

-H


152<br />

2l'ltfno er Pa-j-Kb<br />

'ir^'^-^m+m = Cl:z(v-^+A m. = ^Kb<br />

P-i ^ V p-i y p-i<br />

^ (n4-i)n(n-i) (»-(P - 3)) .^„,^^_,,,^p_.<br />

I. 2. 3 p—I<br />

Sctte er i ben ni)e STffffc bet pbe Sceb, fom vt ville<br />

betegne meb 5p; fatteg nu n-j-i = n, fan er S)} =<br />

n(n-i)(»-2) (n-(p-2)) ^„_^^_,^-^^_,<br />

I. 2. 3 p — I<br />

felgdigcn n^ingtigt bet fnmme Secb i Siffffcu (a4-b)", fom<br />

P vnr i Svffffen (a-j-b)"<br />

ajetegne vi ligelebeg bet (p-j-i)be Seeb meb 0, fno cr<br />

0 = Qa4-Pb = ^Siz2)pb+pb = M:_Lpi,<br />

p P<br />

^ (n-fi)n(n-i) (n - (p - .)) ^,_(p_,,j^^<br />

I. 2. 3 p<br />

,. nOi-i)(n-2) (t.-(p-i)) ^^_^^^<br />

I. 2. 3 p<br />

nltfan bnnnet neingtigt pnn famme 5)ioabe, fom for^cn Q.<br />

. ipvig Seven nltfoo gjfflbcr for 'Pctenfen n, vil ben og<br />

gjclbc for n -j- I •> nu inbfee vi oltfnn ot ben cr olminbclig,<br />

tt)t vi bevifte ben for be ferfte ^etenfer 2, 3, 4, 5, og<br />

fluttc: gjelber ben for ben ste, bo gjelbcr ben og for ben<br />

6te, gjelbcr ben for ben 6tc, ba gjdber ben og for ben 7be<br />

:c. SSort 3nbuctiong; SScviig cr fonlcbcg olminbcligt.<br />

©nnlcbcg er nitfno SSinominl; gormlen beviift for f)e\e<br />

og pofitive Srponcnter; vi inbfee let, ot « bcttc ^ilffflbc of;<br />

brpbeg ben, og vil fun i bet J?ele inbe^olbe n -j-1 Secb. Z^<br />

fffttcg i Ubtvt;ffet for P, p = n4-2, bn bliver ben fibfle<br />

gnctor i SfflSeren n —n = o, nitfno fcrfoinier Scbbct;


eg ligelebeg villc olle fol.icnbe Sceb ^ave famme gnctor og,<br />

pnn (Svunb bcvaf, fovfvinbe.<br />

$. 46. SJilbe vi olminbdigen ubvifle 5Mrtomial;gormlen,<br />

^vig n cntcn var en SBref ellcr ct ncgntivt Zal, fan funne<br />

vi gjere Opcvntioncn ffmplevc vcb nt ffftte<br />

(a-l-b)" = a"(^i-l-^y<br />

b<br />

SBetcgne vi nu — meb x, fnn fommer bet cue on pan i ct;<br />

a<br />

^oert '^ilffflbe nt ubvifle (i -j- x)".<br />

aSnr aSinominl; gormlen nlmecngjfflbenbe, fan ^nvbc vi<br />

n (11 — i)<br />

(l -j- x)" = I -j- nx -j x= -j-<br />

Snb eg betegne benne Siffffe meb [n], fnn vibe vi t<br />

bet ^Diinbfte, nonr n er et ^eelt Zal, nt<br />

[n] = (i-l-x)"<br />

Sigclebeg ville vi betegne<br />

meb [p], og vi vibe bn ogfnn, ot, nnnr p er ct ^celt ?nl, er<br />

[p]== (i4-x)p<br />

Snnne vi 'prcbuctet [n]. [p] og orbne bet cfter be<br />

fvcmfTvibenbe ^Potcnfcr nf x, ibet vi ffftte<br />

[n].[p] = i-j-Ax4-Bx^-|-Cx'4<br />

ftltfnn<br />

= I-j-ii]x4-n(n —])'^x^ 4"<br />

1 ^* ^<br />

p) 4-p(p^^J<br />

J.* ^<br />

np


I 54<br />

A =: n-j-p<br />

n(n —i) p(p—i)<br />

B = --j ~ ^np<br />

I. 2 I. 2<br />

Se 0vrige Soefficicnter funne vi vel ligelebeg ubvifle, bog<br />

vilbe benne Ubvifling vffrc forbunben meb beftnnbig tiltngenbe<br />

JSefvffvlig^cb. gordebigen inbfee vi imiblertib ollcrebc: i) ot<br />

be olle vore fommenfattc of n og p; 2) at gorbtnbelfcn ellcr<br />

®ommenfffttelfcg;'i)]tflObcn vor ben fomme, ^vob cnbog u og<br />

p vor. aSi be^eve nltfao blot i eet '2;ilffflbe ot unberfege<br />

ben, eg funne bernf flutte ot ben gjfflbcr olminbcligt. SSi<br />

villc berfor unberfege, ^vob A, B, C, D --- blive, ^vi*<br />

n og p ere ^elc og pofitive 'Jot.<br />

So i bette ^ilffflbc<br />

fno ec<br />

[n] = (i4-x)-<br />

[p] = (i4-x)i?<br />

[n].[pj = (i4-x)"+P =<br />

.4-(„4_p).4_(^P)^PJZi),.4.__<br />

Senne Siffffc villc vt i 2(nalogie meb be forrige SSetcgndfet<br />

ffftte ligcftor meb [n-j-p], og bo bet for gormeng ©fijlb<br />

er ligegylbtgt ^vnb n og p bctyber, fon er ftebfe<br />

[ii].[p] = [n4-p]<br />

3tf benne fnnlebeg bevifte gorbtnbelfc er bet nu let al;<br />

minbdigt ot bevife SBinomioUgormen. ©fftte vi n = p,<br />

bo cr<br />

Sigclebeg<br />

og nlminbeligt<br />

[n]^ = [2n]<br />

W = [30]<br />

[n]'. — [bn]


fnn cr<br />

155<br />

g-r nu bn et ^cclt 5nl, fom vi ville betegne meb k,<br />

1.<br />

[n]h = (i-Hx)<br />

3tltfna, bn n = y-, er, veb nt ubbrnge ben bte 9»ob,<br />

Kt-0<br />

(i4-x)i^ = [n] = i4-^x4<br />

I. 2. 3<br />

.x'4---.<br />

SSnr Srponcntcn negntiv, ba gjfflbte Soven ogfaa. 95c;<br />

tcgncbe vi ncmlig Slffffcn, ^vovt vnv inbfnt ben negntivc<br />

©tevvdfe —n, meb [—n], fnn vnr<br />

[-n][n] = [-n4-n] = [o] = (i-j-x)» ^ i<br />

2l'ltfnn<br />

^-"^ = [^ = (7+^ = ^^ + ^)-"<br />

ellcr<br />

, IN n (— n — i)<br />

(i 4- x)-" = I — nx ^ X"<br />

I. 2<br />

gelgcligcn blcv gormlen ben fnmme, vnr cnbog .?&inomictg<br />

(Srponent en Sjref ellcr negntiv. SSi funbe ncmlig nu<br />

inbffftte ntter x =<br />

b<br />

— og multiplicerc meb a"<br />

a<br />

Silt. I. ©dv vilbe vi vffre iftnnb til, ^vig n var<br />

irrational, ot gobtgjere gormlen; vi funbe ncmlig i bette<br />

Silffflbe flebfe finbe to ©Vffnbfer, p og q, fom vare ratio;<br />

nale, imellem ^vilfe n laae, og oltfaa ligdcbcg gobtgjere, at<br />

(i-j-x)" laae imellem (t-j-x)p og (i4-x)i. S^ffvmcbc


156<br />

vi nu biffe ©rffnbfer fan meget vt viHe i}inanben, fnn inb;<br />

fane vi, ot nobvenbigviig (i-j-x)" maatte fynve fnmme gorm,<br />

for ot forblive berimellem. ©dv l)vig u vnr tmoginnir,<br />

gjfflbte gormlen; bog 2(nvenbelfen ^crnf, ligefom .Qjcvifct,<br />

fremfffttcg ferft i ben ^eicre 2(ritl)mcti6.<br />

Zili. 2. 3fnvcnbclfcn nf S5inominl;govmlen cr foare<br />

^i;ppig; meb en riiige gornnbring ville vt let vffTC i ©tnnb<br />

til nt ubvifle vcb ben forfPjelligc 3iffffcr. SSi ville ^ervcb<br />

Iffggc SDIffrfe til, at faafnort iSinemictg ^Poteng er en S5ref<br />

eller negativ, cr Stffffen uenbelig.<br />

ipove vi fnolcbeg givet<br />

c C I c /• b"\~"'<br />

I)--7-r=-X - = -(i4--) z=<br />

a-|-b a b<br />

i-l-T<br />

a V a 7<br />

c<br />

a V a ^ a* a^ ~ J<br />

bcrt famme Slffffc vt ubviflcbe for^en (I. §. 65 ?ilt. 2).<br />

II) ©fulbe vi uffrmere beftemme felgenbe ^rrotional;<br />

©teivrdfc<br />

m<br />

YA<br />

fan ville vt ffftte<br />

A = a-j-x<br />

bet vil figc bele A i to Sele, ^vornf ben ene, a, cr en<br />

fulbfonimcn 'Peteng.<br />

?lu er<br />

A = a-j-x<br />

X<br />

Vt Villc ffftte — = y, bn cr<br />

0+0


lu J m 2. •<br />

YA = A'" = -V^a (I -j- y)'" =<br />

K m 2 m yn y y<br />

157<br />

'"/- /^ 1 ^ 1 '^-^'^ "^' I (i-m)(i—2n0 x' \<br />

= ^\^+^+7m^ -7^+ 6~m^ 13+-^<br />

2invcnbcg bcnuc govmcl f (£r. til (Srtroctionen of Subifro;<br />

ben, fan cr m 3, nitfnn<br />

^A=farx4----44-^-—)<br />

y ' 3a 9 a- ' 81 a^ J<br />

gnn Sceb ville nllercbe give cn f)uvtig 21'ppvorimntion:<br />

3<br />

f St. ville vt ubbrnge V^70, bn ffftte vi a = 64, x = 6,<br />

nitfnn ^aveg<br />

4f,4-i._-^4.-5 ^<br />

\ 32 1024 98304 /<br />

2981 2981<br />

= 4 X 1 = 4<br />

98304 24576<br />

:= 4,1212972<br />

Sen fanbc Sffrbic tli-ccr<br />

4,1212853<br />

atffrmcre ^avbe vi cnbnu funbet (lubifrobcn veb ferft<br />

flt beflemme nogle Slaffec paa ben fffbvnnlige 93inabe, ©aa;,<br />

lebeg finbe vi let vcb ot tilfeie to Slnffcr SJJullcr<br />

y7o = 4,12<br />

SJicften bliver 65472, eller egentligen 0,065472. SSi fotte<br />

nltfao<br />

a = 69,934528<br />

X = 0,065472


158<br />

SnbfTrffufe vi og til be tre ferfte Secb of Svffffcn,<br />

foo r)nve vt<br />

J^cr cr oltfoo, f;vig til .53refcng .^eregning onvenbeg<br />

£ognrit^mcr,<br />

log 0,065472 = 8,816056<br />

Clog 69,9345 = 8,155308<br />

Clog 3 = 9,522879<br />

X<br />

log— = 6,494243<br />

S5refen felv 0,000312064<br />

I,<br />

X<br />

I = 0,999688<br />

3-1<br />

log = 9*999864<br />

X<br />

log— = 6,494243<br />

3a<br />

6,494107<br />

^nllct 0,000311966<br />

+ 1<br />

9)Iultipliceveg meb 4,12<br />

1,000311966<br />

4,001247864<br />

100031197<br />

20006239<br />

V'70 = 4*121285300<br />

Ct Stefultnt, fom cnbog i bet fibfle SccimnI er rigtigt.


159<br />

21 lint. a?incniial:gcvmlen faacv i ailminbcligljcb sRaon af<br />

tlicorcma Ntiitoiilaniini CftCr 3- 92 C 11) t 0 U , bcr OUgioCg<br />

fcm beng Cpfinbcv; bog bar ben allcrcbe tibligerc ootret<br />

^afcal og s:. SSviggg befjcnbt, ®et anfortc a3e:<br />

oiig cr af Cnler. S:ibligere og Icttcre er ben bleocu<br />

fnlbfloenbigcn bcoiifl i differential:Dicgningen.<br />

§. 47. SSi funbe nu ubvifle 'P>otcnfen of ct 'Jvino;<br />

mium, ^vor vi bog villc ontoge ot Grponenten er ct l)cdt<br />

og po|itiot ^nl.<br />

(a-j-b4-e)" := (a 4-(b-j-c))" =<br />

a"4-na"-i (b -j- c) -j-" a"-' (b -j- c)^4<br />

n(n-i)(n-2) —(n-(p-i)) „ . , , , ,<br />

-H ~ a"—P(b4-c)pH<br />

I. 2. 3 -- p ^ 1 ^ 1<br />

^vor bet nlminbdige Sceb er bet (p -j- i)te i Stffffen.<br />

Ubvifle vi frembdeg (b4-c)p, bo f)a'i>e vi<br />

(b4-c)p = bp4-pbP-' c4-P'-P~'-'bp-^c'4- —<br />

, P Cp — i) (p — (s — 1)),<br />

-j i ip — S gS<br />

I. 2 S<br />

Set alminbelige Seeb er i (a4-b-f-c)p<br />

n(n-i)---(n-(p-i))Xp(p-i)—-(p-(s-i))<br />

1. 2 p X I. 2 s<br />

X a" — P bp — s cs<br />

©fftte Vt nu n —p =<br />

felgcr, ot<br />

(J, p —s = r, ^vorof<br />

n = q-j-J'-f-s<br />

fnn ^nve vi fom nlminbeligt Secb<br />

n (n - I) --- (cf 4- i) X p (p — 1) —- (1-4-1) ,<br />

—— • — aib^c'<br />

I. 2 p X I. 2 s<br />

^icn nu vil nlle gactorevne p til r-|-i fovfvinbe, bn<br />

be fiubcg baobc i Sffllcr og S^ffvner, og bn cr Scbbct


i6o<br />

n(n—i) (q-f-i)<br />

_i i hiJ—i aq b' c»<br />

I. 2 -- r X I. 2 -- s<br />

©ffttcg cnbnu til for mere ©i;mmetvieg ©fi;lb i ^iffllet<br />

og 97ffvner gnctorcrne i. 2 q, fan ^nve vi<br />

n(n —i) 3- 2. I<br />

al b' c*<br />

i.2--qXi.2--rXi.2--s<br />

5(ltfnn vil (a 4- b -j- c)" beftnne of fnnmnnge Secb of oven;<br />

ftnncnbc gorm, fom vi funbe give q, r og s forffjcllige<br />

SSffrbter, bog unbcr ben SSetingclfe, nt be cre ^ele og pofi;<br />

tive %al og tilfnmmcn ubgjere n.<br />

Silt, giftmlen vil gjfflbe nlminbeligt for Invert 'Po;<br />

li;nomium; t^i vi funbe f. Sr. tnge nf (a -j- b -j- c -j- d)'=<br />

bet nlminbdige Seeb<br />

k(k-i) --- (k-(n-i)) . „^, , , ,^<br />

— at —n (b -I- c 4- d)"<br />

I. 2 3<br />

So nu bet olminbdige Seeb of (b -j- c -J- d)" er fiin;<br />

ben ovenfor, fno cr bet olminbdige Secb of ^ele Ubviflingen,<br />

f)vig vi tillige ffftte k — n = 1,<br />

k(k-i)(k-2)--(14-i)Xn(n —i)--i ,,<br />

• — — al bi C d><br />

i.2--nXl-2--qXi.2--rXi.2--s<br />

eOcr, Inbe vi gnctorcrne 1.2 u gnoc ub t 2ffl;<br />

ler og SJ^ffvncr, og berimob' tilfa'tte 1(1 —i) i, [flo<br />

^nve vt<br />

k(k-l)(k-2) 3. 2. I , ^<br />

1 ^ 3 r: al bl c"- d»<br />

i.2--lXi.2--qXi. 2--rXi. 2--*<br />

f)vor ntter<br />

k = 1 -j- q 4- r 4_ s<br />

og fnnlebeg frembdeg vilbe gormlen for bet nlminbdige Secb<br />

f)ave fnmme ©fiffclfe, ^vormnnge Sele enb >Poli;uomict bc(<br />

ftob nf.


i6i<br />

§. 48. gor pnn cn nemmcre 93Ionbe, cub ben, ber<br />

ovenfor er ongivcn (I. §. 124), ot beregne Sogarit^mcrne,<br />

nnvcnbeg ogfoo en Diffffc; Ubvifling. SSi villc ffftte<br />

log([4-x) =z A-j-Bx-f-Cx=4-Dx^-j<br />

jjer fee vi, at for x z=^ o, er log i = o, nltfao A<br />

i^ o, og felgdigcn<br />

log(i + x) = Bx-f-Cx^4-Dx3-j<br />

SSi ^ove nu (I. §. 126)<br />

log(i-j-x)^ •=z 2log(i4-x)<br />

log(l-j-x)- = log (l 4-2x4-X')<br />

ffietcgne vi nitfnn 2x4-x' meb z, foo cr<br />

2 Bx 4- 2 Cx^ 4- 2 Dx' -1 =<br />

Bz4-Cz-4-Dz^-j =<br />

B (2 X -j- x^-) -j- C (2 X -j- x=)^ -I<br />

Orbneg ben fibfle 3vffffe cfter be fligenbe QJotcnfer of<br />

X, fnn ^ove vi<br />

2Bx-j-2C'x'-j-2Dx3 4-2Ex*-j =<br />

2Bx4- Blx^4-4C)x'-j- C\x*-j<br />

4-4CJ -f-sD) 4-I2D(<br />

4-16E)<br />

3Cltfao (§. 44)<br />

2B = 2B<br />

2C = B-J-4C<br />

2D=z=4C4-8D<br />

2E 1= C4-12D4-16E<br />

0. f V.<br />

J?craf ville vi ^ntet funne ublebe for B; men<br />

C •= —iB, D = -\-\B, E = —^B o.f V.<br />

.Snbfffttcg biffe SSffrbier, bliver nitfno<br />

log(i-f-x) = B(x —ix'-j-ix'—ix*-| )<br />

II. II


§. 49. gftevfom B fooer forfFjcUige SSffrbier, cr^olbe<br />

Sognrit^mcrne forffjeltig ©terrdfe, eller ^erc til forffjcllige<br />

©yflcmcr (I. §. 124). 3blonbt olle ©i;ftcmer funne vt imib;<br />

Icvttb vfflge eet, ^vig ©runbtol vi uffrmere ffulle beftemme<br />

og ^vor B = i; bette ©i)ftem folbeg be noturlige<br />

Sogorit^mer, og betegneg meb log. nat. ger .^ort^ebg<br />

©fi;lb ville vi blot betegne bem meb Log.<br />

Silt. I. 23i ^ave nitfno<br />

Lcgii+x) = X—Vx=4-i-x'—ix* -<br />

eg ^crnf, veb ot ffftte x = — x<br />

Logii—^) = — (x4-'x^-4-ix'4-ix* )<br />

5fltfno cr<br />

Log ( ^-—^ J = Log (t 4- x) — Log (i — x) =r<br />

2(x4-ix'4-ix'-j )<br />

Silt. 2. ©fulle biffe Slffffer convetgere, bo moo x<br />

Vffre en egentlig ^tet; jo minbre ben togeg, befto ^urtigete<br />

convergerc Svffffen. ©om ^>reve pon be Stcgningg; 2fffort;<br />

ninger, mnn fan onvcnbe, tjcne L>og 10.<br />

Log 10 := Log 2 -j- Log 5<br />

.3^cn2=(l)'xf 5 = fx4 = |x2^<br />

nltf'nn<br />

4 9<br />

Log 2 = 2 Log j- Log —<br />

3 8<br />

5<br />

Logs = Log j-2Zo^2<br />

4<br />

©fftte vi nitfnn<br />

i-t-x 4 9 5 ^<br />

7-^ — I' = i' = 7' ^'' "


3lltfnn<br />

1 I<br />

7 1"<br />

hog^ = 2f--|-- -A—--H ^<br />

" 3 V7 3-7*^5.7^ J<br />

9 /" I , I , I , ^<br />

Log- = \r7+3T^+5Ti7^+—V<br />

5 /'l . I I "\<br />

"4 V9 ^3-9' ' 5.9^^ y<br />

.fjcrnf felgcr nltfan<br />

Log 2 = 2<br />

= 0,6931471805<br />

Lo^5 =^ 2 Log 2<br />

^ V9^3-9^^5.9'^ 7<br />

= 1,6094379124<br />

io^ 10 = 2,3025850929<br />

163<br />

Slnin. Siffe noturlige Sogarit^mcr, fom og faac sjiaon<br />

af t;ppcrboliffe, finbeg i flere ©amlinger af aa»:<br />

ler, f. er.<br />

©ci)ulje'g ©ammlung Icgar, trig. K. Safcln, iftet<br />

a()dl.<br />

§. 49. gor ot beftemme ©runbtnllet for be nnturlige<br />

Sogarit^mcv, ville vi onvcnbe Slffffen Log (i-j-x), fom<br />

vi ville betegne meb y, oltfoo<br />

y = X —i-x'4-^x^—ix*^<br />

II*


164<br />

gor ^crof ot finbe x, onvcnbe vi ben ?9?ct^obe, bet<br />

folbcg 3vfffferneg 3"«ccfton; vi ffftte nemlig<br />

X = ay 4- by^ 4- cy» 4- dy* 4<br />

og beftemme a, b, c, d efter be ubeftemte Coefficicm<br />

terg 5}iet^obe (§. 44). 3nbf«tte vt SSffrbien of x i tUcth<br />

ten for y, foo ^ove vi y =<br />

ay-i-b )y'-t- c jy'4-<br />

— laM — ab I —<br />

+ia3 ; 4-<br />

* , f<br />

— i-a<br />

d \y*-fac<br />

1 —<br />

ib'l [ —<br />

L^b j<br />

m^aa ex<br />

a = I<br />

b —la^ = o<br />

c — ab -j- i a^ = o<br />

d_ac —ib^ 4-a^b —la* = O<br />

+<br />

4-i<br />

e ' \7'<br />

ad<br />

be 1<br />

ab^'<br />

a-c<br />

a^b 1<br />

e _ ad — be 4- ab^ 4- a= c — a^ b 4- |a« = 0<br />

ijcrnf felgcc<br />

3lltfnn er<br />

a = I<br />

2 2<br />

I I<br />

6 2.3<br />

24 2. 3. 4<br />

I I<br />

120 2.3.4.5


^ = ay+iy=-|-cy'4-dy*4-cy5-|<br />

J 65<br />

1.2 1.2.3 1.2.3.4 1.2.3.4.5<br />

©fftte vi nu Zo^(i-j-x) = y = i, fnn er i-j-x<br />

©runbtnllet; bette ville vi tetegne meb c, nitfno<br />

e = 14-X = i4-i-i 1 1<br />

I. 2 I. 2. 3<br />

= 2,718281828459<br />

§. 51. gor divert nnbct ©t;ftem enb be noturlige So;<br />

gnrit^mer cr B fterre ellcr minbre enb i. €r ©runbtnllet a<br />

I 4-x<br />

givet, ville vi let finbe B. ©fftte vt nemlig —— = a,<br />

1 — X<br />

a — I<br />

foo er omvenbt x = --r—. eg, bo vt ^ove<br />

SL —J— I<br />

foo er olminbdige<br />

^°S (^-1) = ^B (x4--^x3 4-f X-—)<br />

^vorof<br />

-!(^)+KS)'+i(^)"--i<br />

Slffffcn er convergerenbc; vi ville ffftte ben, multipliceret<br />

meb 2, liig M, ^vorof oltfoa felgcr i = MB og B = —<br />

©terrdfcn M folbe vi ©i;ftemetg 93iobul, for a = 10<br />

eUcr be olminbdige Sogovit^mer blcv<br />

M = 2 1^4--^"-4-^4- —<br />

In 3.11^^5. Il*~


166<br />

S i t f. SSi funne imiblertib finbe tOJobuIcn Icltcve pan<br />

felgenbe 9)conbe: SSi vibe, at nf ^vilfetfom^dft 'Jnl m er<br />

log ni = B Log m = — Log m<br />

o " INI *<br />

©ffttcg nitfnn m = a, fnn f)nve vi<br />

I = —Log a.<br />

nltfoo<br />

M = Log a<br />

gelgcligcn cr M intet ubcn ben noturlige Sogorit^mc of ©runb;<br />

toilet i bet givne ©i;ftem. ©nolebcg er for be olminbdige<br />

Sogorit^er<br />

M = Log lo ^= 2,30258509<br />

Silt. 2. gor oltfao ot finbe be olminbdige Sogortt^;<br />

mcr of be nnturlige, bivibereg biffe meb M, ellcr og mul;<br />

tiplicercg meb<br />

— =z 0,434294481903<br />

§. 52, Ogfoo be trigonometrifFe gunctioner Inbe fig<br />

ubvifle vcb Stffffcr, fom tjene til, enten ot beftemme bcm,<br />

noor SSinflcn ellcr SSuen cr given, cller omvenbt, noor en<br />

gunction er given, bo ot beftemme ben tilfvnrenbe 25ue ellcr<br />

aSinfd.<br />

5nge vi gormlerne<br />

sin (a -j- b) =:= sin a cos b -j- cos a siu b<br />

cos (a -j- b) = cos a cos b — sin a sin b<br />

(5rig. §. 6)<br />

og ffftte uu bexi fnovd a fom b ligcftor meb x, fno cr<br />

sin 2x = 2 sin x cos x<br />

cos 2 X = cos X* — sin x'<br />

gormler, fcm vi nllercbe f;nvc funbet ovenfor (-^rig, §. 9).


167<br />

©fftte vt frembdeg a = 2x, b =: x, fnn ev<br />

siu 3 X sin 2 X cos x -j- cos 2 x sin x<br />

= 2 siu X cos X- 4" cos X•• sin x — siii x^<br />

^= 3 cos X- sin X — sin X'<br />

cos 3x cos 2 X cos X — sin 2 x sin x<br />

Sigdcbeg<br />

= cos x' — sin X- cos x — 2 sin x- cos x<br />

cos x' — 3 sin x- cos x<br />

sin 4 X = sin 3 x cos x 4" cos 3 x sin x<br />

3cos %^ sin X — sin x^ cos x -j- cos x^ sin x<br />

= 4C0SX' sinx — 4sin x' cos x<br />

COS4X COS3XCOSX — sin 3X sinx<br />

— 3 sin x^ cos X<br />

cosx* — 3sin x^ cos x- — 3cos x' sin x*<br />

COS X* — 6 sin x' cos x^ -j" *iii x*<br />

^00 fnmme 93iaabe funne vi ubvifle<br />

-j- sin X*<br />

sin 5 X = 5 cos X* sin x — 10 cos x^ sin x' -j- ^'i^ ^'<br />

C0S5X cosx*—10 cos x^ sin x^-j-5 cos X sin X*<br />

sin 6 X = 6 cos x^ sin x — 20 cos x^ sin x' -j- 6 cos s<br />

sinx'<br />

cos6x = cosx^ — 15cos X* sinx--f-15cosx-sinx*<br />

— sin x''<br />

Sen olminbdige gormel, ^vorunber olle biffe Ubtri;f funne<br />

fnmmenfnttcg, er felgenbe t<br />

n(n—i)(n—2)<br />

Sinnx = ncosx"—'sinx— cosx"—'sin >:"<br />

I. 2. 3<br />

, n(n—i)(a —2)(n—3)(n —4) „ . • s<br />

•f-^— • — cosx" —•• siux^


168<br />

n (n — i)<br />

cos nx = cos X" cos x"—' sin x*<br />

I. 2<br />

n(n-i)(n-2)(n-3) „ , • ,<br />

4- cos X"—* sin x*<br />

I. 2. 3. 4<br />

u(n-i)(n-2)(n-3)(n-4)(n-5) .<br />

—cosx"—"sinx'<br />

+ K.<br />

I. 2. 3. 4. 5. 6k<br />

SSi funne let veb en fulbftffnbig ^inbuctien bevife biffe<br />

germlerg ©ylbig^eb for et^vert n, nnnr bet blot er et ^celt<br />

og pofitivt Z.aL SSi ^ove nemlig<br />

sin (n -j- 1) X = sin nx cos x -f- cos nx sin x<br />

n (n — 1) (n — 2)<br />

n cos X" sin x cos x" —^ sin x*<br />

I. 2. 3<br />

n(n —i)(n —2)(n —3)(n —4) .<br />

4 cosx"—*sinx'+---<br />

I. 2. 3« 4« 5<br />

n (n — 1)<br />

+ cos X" sin X cos x"— - sin x*<br />

I. 2<br />

n(n —i)(n —2)(n —3)<br />

_i cos X" — * sinx* -}<br />

I. 2. 3. 4<br />

©omle vi be Seeb fommen, fom ^ovc fomme gjrponent, of<br />

sin X og cos x, fno er<br />

sin (n -j- 1) X =<br />

, , N . Ol-}-1)11(11—i)<br />

(n 4- i) cos X" sm x cos x" — - sm x'<br />

I. 2. 3<br />

(n-j-i)n(n-i)(n-2)(n-3) .<br />

H cosx" — * sinx*<br />

I. 2. 3. 4. 5<br />

3(ltfflo neiogtigt bet fomme Ubtri;f fom for^en; blot, ot<br />

n -j- I (looer ollevegne iftebctfor n.<br />

Sigclebeg<br />

cos (n -j-1) X =: cos nx cos x — sin nx sin x


n (n — i)<br />

cos x" + ' — cos X" — ' sin x-<br />

I. 2<br />

n(n —i)(n —2)(n —3)<br />

-j cos X" —' sin X'<br />

I. 2. 3. 4<br />

169<br />

n(n —i)(n-2)(n-3)(n-4)(n-5) cos X" —*MI1 X*<br />

I. 2. 3. 4. 5. 6<br />

+ -<br />

n(n — i)(n — 2)<br />

— •ni ncosx"—' sinx^-j cosx"—^ sinx*<br />

I. 2. 3<br />

P(n— i) (n — 2) (n — 3) (n — 4)<br />

!• 2<br />

vf<br />

(n4-i)n<br />

=: cos X" "T • cos X" —' sin X*<br />

I. 2<br />

(n-j-i)n(H—i)(u —2)<br />

-1 cos X" — 3 sin X*<br />

I. 2. 3. 4<br />

(n4-i)n(n —i)(n —2)(n —3)(u —4) .<br />

— • cos X"—' sin x°<br />

I. 2. 3. 4. 5. 6<br />

+<br />

Otter neie et ccngortct Ubtri;f, fom bet forl)en ubviflcbe<br />

for cos nx.<br />

SSi ville oltfao olminbcligt inbfee, nt ovenftnncube gorm;<br />

ler gjfflbe, n vffre ^vilfctfomf;elft ^eelt pofftivt Zal<br />

§. 53. linvenbe vi biffe gormler til S&cftemmclfcn nf<br />

©inug og Sofinug, nnnr SBucn er given, fnn funne vi f'fftte<br />

z at vffve ot uenbelig liben 23uc; for en foabon fnlbcr ©i;<br />

nug fnmmen meb SBuen, Softnug meb i, eller vi ^nvc<br />

sin X z=z X; cos x = i<br />

Snber og nu ^ove ot beftemme sin z og cos z, fao ffftte<br />

vi z = nx, ^vor bo neibvcnbigvitg n bliver ucnbdigt flor;


170<br />

men bo en uenbelig flor ©tatrdfe veb Cn enbclig ©t«rrelfe<br />

^verfen formereg eller forminbfTeg, foo mono vi nnfee n — 1,<br />

n — 2, n — 3 jc. olle nt vffre ucnbdigt (tore, oltfna ligc;<br />

ftore meb felve n; oltfoo<br />

n^ x' n' x"<br />

sin z = n. X • I. 2. 3 1. 2. 3. 4. 5<br />

Stgdebeg<br />

z' z^<br />

1.2.3 1.2.3.4.5<br />

z* z* z*<br />

cos z I 1 —<br />

1.2 1.2.3.4 1.2.3.4.5.6<br />

93uen z fTol vffre ubtri;ft i Sffngbe, ubmoolt meb Slobiug<br />

fom Sen^cb; er ben ubtri)ft i ©robcr og ^olber Z°, foo, bo<br />

380° rectificccebe etc foe 3tobiug i Collet 5r, ^ove vi<br />

Z°<br />

Z = -ff<br />

180°<br />

So nu 5r'g ©terrdfe cr befjcnbt (I. ©com. §. 150),<br />

foo funne vi inbffftte benne SSffrbie, og er^olbe foolebeg cn<br />

cenvcrgercnbe 9tffffe for ot beftemme sin z og cos z.<br />

%Hl.<br />

finbeg<br />

3tf be funbne Ubtri;f for sinz og cosz fan<br />

cosz sin z<br />

Sog vilbe benne Sivifion meb Secimol; SSrefcr of mange<br />

Secimolcr vffre vnnfFdig og vibtleftig; bebft ubvifle vi ber;<br />

for en 5)tetf)obe for umibbdbnrt nt finbe tg z.<br />

nt onvcnbe Siffffcrne<br />

SSi ^nve veb<br />

tg Z =<br />

^<br />

z<br />

z' z*<br />

4<br />

1.2.3 1.2.3.4.5<br />

„ ;<br />

Z^ Z'<br />

z'<br />

1.2.3.4.5.6.7--<br />

Z«<br />

I— — 4- —<br />

1.2 1.2.3.4 1.2.3.4.5.6


ger ot Ictte benne Ubvifling ffftte vi<br />

b = -^ c = ^<br />

1.2 1.2.3 1.2.3.4<br />

1.2.3.4.5 1.2.3.4.5.6<br />

I<br />

!C.<br />

171<br />

3(ltfflo cr<br />

I — cz* -j- ez* — gz^ -j<br />

tgz I — bz=-j-dz* —fz«4--<br />

Set fommer nu blot nn paa, ot ubvifle Srefen, og vi<br />

ville cnbnu, for ot lette benne Operation, ffftte a^ = y.<br />

So er<br />

I —cy-j-ey'—gy^4-ky*-| __<br />

i-by4-dy^-fy^-|-by*H<br />

l4-By4-Cy^4-Dy»4-Ey*+---<br />

^vor B, C, D, E blive ot beftemme efter be ubeftemte<br />

goefficicntetg tOtet^obe. Sen ferfte Coefficient A ^nvc vi<br />

flror fat liig i, bo vi inbfee, ot, vcb ot gjere y = o,<br />

a>refcn bliver i.<br />

STiUltipliccre vi bo meb 9?ffvncren, fao ^ove vi<br />

J — cy 4- ey' — sy' -|- ^y* =<br />

i-hB)y+ CW^-1- DW3 4- EW*---<br />

— bj —bBJ —bcf —bD/<br />

4- d) +dBJ 4-dcJ<br />

— f) — fBl<br />

4- hi<br />

^crnf felgcc oltfao<br />

B = b — c<br />

C = bB — d 4- e<br />

D = bC —dB-j-f—g<br />

E = bD —dG4-fB —h4-k


172<br />

SSi fee let, ^vortcbcg ben ene Soefftctent felgcc nf ben<br />

onben, og funne beregne bem, vcb ot inbffftte SJffrbierne af<br />

b, c, d . ©oolebeg ec<br />

I I<br />

B = 1.2 1.2.3<br />

D =<br />

1.2 I. 2. 3.4 I. 2. 3. 4.5<br />

C B I<br />

1.2 I. 2. 3.4 1.2. 3.4. 5- 6<br />

0. f. V.<br />

I<br />

1.2. 3.4.5> 6.7<br />

I 2 17 63<br />

dHex B = —, C = —, D = -^, E =<br />

3 15 315 2835<br />

0. f.». Snbffftteg biffe SSffrbier og tillige y = z^, fan ec<br />

,1 ,2 ,17 ,62<br />

ts z — z4—z' 4— z* 4 ^^ 4 z* 4<br />

° 3 15 315 2835<br />

Sigdcbeg beregne vi Sotongenten veb ot ffftte<br />

cosz I—bz'-4-dz*4<br />

eotz = = -4 r<br />

sm z z — cz* 4- ez* -J<br />

= i. .^'i-^>y-hdy^-fy^4<br />

z I —cy-j-ey^—gy^<br />

©fftte vi nu otter bette a3ref;Ubtri;f ligeftort meb<br />

i4-By4-Cy^4-Dy^4<br />

jflfl cr ^er<br />

B = c —b<br />

C = cB — e -f- d<br />

D = cC — eB-j-g — f<br />

E = cD —eC-j-gB-k-j-h<br />

0. f V.


Sctnf<br />

eacr<br />

C =<br />

I<br />

1.2. 3<br />

B<br />

1.2. 3<br />

B = --, C =<br />

3<br />

3fltfnn er<br />

I<br />

cot z =r= —<br />

I<br />

1. 2<br />

I 1 '<br />

1.2.3.4.5 ' 1.2.3.4<br />

0. f V.<br />

-—, D = - — , E=5=-<br />

45 945<br />

z z' 2z' z'<br />

173<br />

I<br />

4725<br />

z 3 45 945 4725<br />

Sftebet for z ffftte vi beqvemt i biffe gormler for 5on;<br />

gentcn og Cotongenten ligefom ovenfor<br />

2 = -VT<br />

i8o°<br />

Silt. 2. SJilbe vi onvcnbe biffe gormler til Sereg;<br />

ning of noturlige ©inug; og ?ongeng;'5obeller,<br />

fan bc^evebe vi ene ot regne ©inug og Cofinug til 30°.<br />

goreftille vi og ncmlig ©inug fom en Sinie (^rig. §. 3),<br />

foo, bo C^orben for 60° er ligcftor meb 3lobiug, er sin 30°<br />

= i', fatte vi oltfoo a = 30", b = z i gormlerne<br />

ffl og VI (5rig. §. 7), foo ec<br />

cos z z^ sin (30° -j- z) -j- sin (30' — z)<br />

sin z = cos (30° — z) — cos (30° -j- ^)<br />

ijeraf<br />

sin (30° -j- z) = cos z — sin (30° — z)<br />

cos (30° 4" z) cos (30" — z) — sin z<br />

3tltfaa funne vi veb en ©ubtroction er^olbe ©inug og £0;<br />

finug of olle SSinfler inbtil 60°; be evcigeg ©inuffer finbeg<br />

imellem be ollercbe beregnebe Cofinuffer, og omvenbt.


174<br />

SigelcbeS er bet tilftrffffdigt ene ot beregne 'Songcntct<br />

og Sotottgentec til 30°. SSi ^ove ncmlig (§. 9 XVlii)<br />

° 1 — tg a^<br />

3(ltfoo ogfoo<br />

1 — tg a*<br />

cot 2 a = =: •?, cot a — -I- tg a<br />

2 tg a<br />

©fftte vi a = 30° — z, foo er<br />

cot 2 a — cot (60° — 2 z) = tg (30° 4" 2 z)<br />

= i cot (30° — z) — i tg (30° — z)<br />

^vorof ba alle 2ongcnter fro 30° til 90° lobe fig beregne.<br />

Si f)ellec be^eve vt for ©econtcr og Cofeconter ot ubs<br />

vifle fffregne gormler, t^ biffe funne ogfno finbeg vcb cn<br />

©ubtroction. 5oge vi ncmlig<br />

cos 2 a := 2 cos a' — i<br />

eg bivibcre meb<br />

sin 2 a : 2 sin a cos a<br />

foo er<br />

ellcr<br />

cos a I<br />

cot 2 a = -T—<br />

sin a sin 2 a<br />

= cot a — cosec 2 a<br />

ffftte vi 2 a = z, foo<br />

cosec z = cot^^z — cot z<br />

©ffttcg nu otter Ijcri z = 90° — z, fno cr<br />

sec z =: cot (45° •*- V z) — tg z<br />

S111. 3. gor ^cnffgtgmffgjigen efter ovenftooenbc gorm;<br />

ler ot fere .Qjecegningen for et ftort 2fntol trigonometdfTe gunc;<br />

tioner, fom ?;ilffflbct vor, ^vig vi ville beregne ^nbellcr, var<br />

bet lettefl eengong for olle ot ubrcgne Cocfficienterne, og mul;


175<br />

tiplicere bii^c meb be tilfyrtvenbc Sjfponcntec af —-; cnf^tscr<br />

of biffe fnnlcbcj ubrcgncbe ©terrelfcr bc^evcbc vi ba blot nt<br />

multiplicere mci ben bev;il ^ercutc 'poteng nf Z°.<br />

§. 53. SSove nltriinbcligc tvigonomctvifTe 'Jnbcller cre<br />

ortificiclU D; Sognritl;mcrne af gunctionerne, men iffe<br />

felve gunctionerne, cre nuijionc (tvig. $. 4). 3fltfnn ffulle<br />

vi, eftcrnt be vnre funbne, fege Sognvit^mcrne. Sog feller<br />

fovbnnbc vi biffe Operntioner i een, og flvffbtc ftvnr i en<br />

Siffffe nt frcmftille log sin z, log eos z jc.<br />

SSi ^ve<br />

+ 1.2.3 1.2.3.4.5<br />

Scttc Ubtn;f mnn oplefeg i gnctorer, for berpnn at onvcnbe<br />

Sogovit^mer. SSi ^ave feet (§. 24), ot 3Gqvationcrncg<br />

Optegning funne onfeeg fom en 9}iflabe ot finb< ct 'Probuctg<br />

goctorer. ©fftte vi oltfao<br />

1.2. 3 I. 2. 3.4. 5<br />

fan inbfee vi, at z flrar er cn gnctor, eQcr ot z = o cr<br />

en Slob of Seqvotionen. SSi ^ave oltfao cnbnu<br />

at oplefe.<br />

1.2.3 1.2.3.4.5<br />

.^evi ffftte vi z- = —, foo er<br />

X<br />

I . I<br />

1.2. 3.x 1.2. 3.4.5. x^<br />

Sctte Ubtrpf leber ub i bet Uenbdige. Sen ^eicfte "Poteng<br />

cr x", multiplicere vi ^ermeb, bliver Seqvgtionen


176<br />

^M — 1<br />

x» — = o<br />

1.2.3<br />

So ben cc of cn uenbelig ^ei ©rob, bliver beng 9lebbcc<br />

ucnbdigt monge. SSi funne imiblertib let efterfpore biffe:<br />

gor z =: o fonbt vi ferft Ubtvyffet ot blive o, b. e. ©i;<br />

nug of en SBue ftoc 0° er o, ligelebeg vibe vi, nt ©inug<br />

flf 180°, 360°, 540° er o; inbffftte vi oltfoa i gormlen<br />

z = 5r, = 257, = 3a- o.f v., b. e. 180", 360°,<br />

540° e. ftV. rectificcrebe, er^olbe vi ligelebeg o, oltfoo eve<br />

3?ebberne<br />

I I I I<br />

z* TT^' 4?r^' 9'^^<br />

eg oltfno moo 5@qvotionen Inbe ffg fvemftille vcb<br />

Sivibere vi ^er otter meb x", ellcr f)vcr goctor meb x,<br />

foo ^ove vi<br />

V^~X!rV\.^<br />

eller er<br />

4^^V V 9^^'J<br />

Sigclebeg funne vi oplefe<br />

1 , I<br />

cos z = I z^ -j z*<br />

1.2 1.2.3.4<br />

I. 2. X 1. 2. 3.4.x-<br />

smz<br />

©fftte vi nemlig bette Ubtri;f ligeftort meb o, og multipli;<br />

(cre meb x", bo ^ove vi ^qvotionen


x» f — o<br />

1.2<br />

177<br />

Sa cosz = o, nanr z = ITT, = i^, = I ir<br />

o.f v., faa eve Siebbcvnc for benne S^qvation:<br />

X = --, = -'^-, = - — !C.<br />

oltfaa finbeg vcb famme gornnbringer, fom forljcn<br />

•Sage vi altfaa ^craf Sogarit^merne, faa cr<br />

Log sin z = Log z 4" Log f I ;• j<br />

+ Log(.-^^+Log(^,-^^+..<br />

Log cos z = Log ^i - ^ j 4- io^- ^i _ ^ j<br />

©fftte vi ^cr z = —-rtr = -—;—jff,<br />

180° 2 X 90°<br />

ba er<br />

Z° /^ Z^ "N<br />

Lo,.siaz = io^—,r4-io^(^i-^<br />

+<br />

Zo^cosZ = Log(\~—'^+Log(\~^-,'^<br />

-f- Zo^ ( I ''—- ) 4- Lo^ ( I )<br />

V 25.90 V V. 49.90 V<br />

II. 12


178<br />

5;oge vi nf Stiffen for Zo^sinz be to ferfte Secb, ba<br />

cre biffe<br />

Log Z -j- Log TT — Log i8o 4- Log (i8o° -j- Z)<br />

4- Log (i8o° — Z) — 2 Log i8o<br />

= Zo^ Z 4- Zo^ (i8o -f- Z) -j- Log (i8o — Z)<br />

4- Zo^- ;r — 3 Log i8o.<br />

Sigclebeg for Log cos z er bet ferfle Seeb<br />

Log Q - ^ ^ = Log (90 4- Z) 4- Log (90' - Z)<br />

— 2 Zo^ 90.<br />

Se 0Vrige Sceb ubvifleg i 9t«ffcr, og bn fffttcg for ^ort;<br />

Z<br />

^ebg ©fi;lb — = V. Stffffe; Ubviflingen fnn bebft fore;<br />

tngcg efter gormlen Log (1 — x) (§. 49. 5ill. i), ibet vi<br />

ffftte efter^nonbcrt of Slffffen for ©inug<br />

ia f)ave vi<br />

V2 V^ V'<br />

Log (.--^ = - r:^4-^4-l!-4._.^<br />

^V i8o^-y ^4^^2.4*^3.4^^ J<br />

"••"' C-lsj)=- Ci^"^^^"^^!^-'-<br />

0. f V.<br />

= _ y^C~-h- + ~ + '-A<br />

V4'^6^^8^^ J<br />

V4*^6*^8*^ J


0. \. V.<br />

Sigdcbeg for Cofinug blive 3lffffevne<br />

179<br />

'^s{'-^) = -(ii+J7+^+"")<br />

^°^(—«^i?) = -(7^+^'+^?+")<br />

= -v


180<br />

— V'» 0,0000001943<br />

— V " 0,0000000100<br />

— V'* 0,0000000005<br />

Log cos Z" = Log (90 4- Z) 4- Log (90 — Z)<br />

-j- 1,0003806593 — ID<br />

—Y^ 0,2337005501<br />

— V* 0,0073390158<br />

—v« 0,0004823589<br />

—v' 0,0000387948<br />

— v'"^ 0,0000034083<br />

— v'^ 0,0000003143<br />

— v'* 0,0000000299<br />

— V'8 0,0000000029<br />

— V" 0,0000000003<br />

gor Sogorit^mcrne of 'Songenterne, Cotnngenterne, ©c;<br />

contevne og Cofeconterne bc^.eveg ingen fffregne Stffffcr, ba<br />

biffe finbeg let vcb ben blotte ©ubtroction nf be givne, ifelge<br />

be ovenfor fremfatte gormler (5rig. §. 2).<br />

Sill. Stffffcrne ville give be noturlige cller ^i;perbo«<br />

liffe Sogorit^mer of ©inug og Cofinug; for ot finbe briggijTe<br />

Sogorit^mcr mootte vi multiplicere meb 0,4342944819<br />

eller og onvenbeg felgenbe Siffffe<br />

log sin Z° z=: log Z 4- log (i8o° 4- Z)<br />

4-log(i8o° —Z)<br />

-f-3/7313323574<br />

—V 0,0700228266<br />

— V* 0,0011172664<br />

— V* 0,0000392291<br />

—v' 0,0000017293<br />

— V 0,0000000844


— V " 0,0000000043<br />

181<br />

— V' * 0,0000000002<br />

ligelebeg<br />

log cos Z° = log (90° 4-Z) 4-log (90 —Z)<br />

4-6,0915149811<br />

— v^ 0,1014948593<br />

— Y* 0,0031872941<br />

— v^ 0,0002094858<br />

— v^ 0,0000168483<br />

— v'" 0,0000014802<br />

— V " 0,0000001365<br />

— V' * 0,0000000130<br />

— v'® 0,0000000013<br />

— V* * 0,0000000001<br />

Sn for ©inug og Coffnug i 'Sobeacrne flebfe ^enffftteg be<br />

beeabiffc Complementer (^rig. §. 4), fno ere biffe Slffffer<br />

ollercbe foregcbe meb 10, fao ot be umibbelbart give be to;<br />

bulnciffe Sognrit^mei;.<br />

2(nm. en ubforlig Itatet fra 10" til 10" of be natndige<br />

Sogantbmc s ©inuffer K. finbeg i<br />

Benj. IJrsmi Trigonometria Colonise 1624.<br />

.^craf l)aoeg ct 3tftrt)E, men fun for \)vett aJlinut eg<br />

meb 7 ®ccimaler, i<br />

©cbuljc'g ©ammlung logaritl;mifc^er:tvigonomctrij<br />

fcbcr Xafeln.<br />

5 enfelte 2;ilfo8lbe ere biffe ttabettec vigtige; men<br />

til faboanligt S8rng anbefalc be bviggiffe fig.<br />

§. 55. Sigefom vi af cn given S&ue f)ave funbet be<br />

ttigonomctdffe gunctioner, funne vi omvenbt of biffe finbe<br />

S5uen. SSi onvenbte ^ertil Siffffe ;5fnvcrfionen (§. 50); fno;<br />

(cbcg Vffre given f. Sr.


182<br />

I 3 17<br />

tgz =r z-j z'4 z^H z'4 '-<br />

^ '3 15 315<br />

©fftte vi tg z = t, fno ville vi ffftte<br />

z :=: at4-bt^4-ct'4-dt*4-et5-j-.fts4 :<br />

bo er t =<br />

al-j-bt^4- c )t'4- d)t*4- e jt^-f f<br />

3(ltfno<br />

a = I<br />

b = o<br />

-j- ac I 4" ^^<br />

+ T\aO 4-|a*b<br />

c-j--|^a ^ o<br />

d-j-a^b = o<br />

e-J-ab'-j-ac-j-Aa* = O<br />

f4_4.b5 4-ad4-fa*b 3= o<br />

0. f. V.<br />

.^erof ville vi ublebe b = o, d = o, f = o, b. e.<br />

(tile lige QJotenferg Coefpdentcr blive o, oltfno bortfnlbe biffe;<br />

berimob ^nve vi<br />

a = T . c = -4., e = i, g = —fo.fv.<br />

(lltfoo<br />

z = t-it'4-ii* —-ft'4<br />

Ziil. 3nbf«tte vi i ben gormd z = 45°, fan cr<br />

t = tg45° = I, z = 45^ rectificerebe AJT, oltfno<br />

iy := i-i4-i —f-l-iH<br />

Senne Siffffe vilbe imiblertib fnore longfomt convergerc, og<br />

fun meb megen gKa^ic give n- nogcnlunbc rigtig.<br />

Sflge vi cn JSue, m, nf ben ,?5ciTnffen^eb, nt tgin<br />

= T, fna ec


2tgm 5<br />

tg2m — tg . . in= . ^^<br />

I<br />

2 tg m I20<br />

^^ I—tg2m- 119<br />

183<br />

SSi cre faalebeg fomne til en SSue iffun libct fterre enb<br />

45°, bn 5angentcn fung er libet fterre enb i; vi ville be;<br />

tcgne ben meb A, og ffftte frembdeg A —45° = B;<br />

faa cr<br />

tgB = ^^-=^ = -^ (5cig. §.8.xm).<br />

» tgA4-i 239<br />

©fftte vi nu<br />

45° = A —B =: 4m —B,<br />

fan, raor vi beftemme A og B, rectificcrebe, veb ipjfflp of<br />

Slffffcn, vil gorfTjeaen imeUem biffe to Staffer ubtri;ffe 45°<br />

rectificcrebe; oltfna, bo sr = 180° = 4X45° cectifi;<br />

ccrebe, er<br />

I T . I I .<br />

s- = 16 5 3.5' 5.5' 7.5'<br />

(I I . I<br />

1239 3.239 5.239'<br />

jjernf Inber nitfnn 3- fig meb cn ^ei @rob of S^eiagtig^cb<br />

finbe, eg Inngt lettere enb ovenfor (I. ©com. §. 149 og<br />

150) er viifl.<br />

§. 56. Se (§. 53) fremfntte Siffffcr ville, jo minbre<br />

23uen cv, meb befto fffvre Secb give ben trigonometriffe gunc;<br />

tion neic. SSi vifle nntnge, ot z ^olbcr foo fan ©vnbcr, ot<br />

vi meb ben Sleingtig^eb, vi enffe bet, funne ffftte<br />

sinz 3=z z—iz' = z (i—-J-z')<br />

tgz = z-j-iz^ = z(i4-iz'>


184<br />

f)vor vi nltfan bortfofte z' og nlle ^«icre ^otenfci: of z.<br />

'5nge vi tillige<br />

cos Z = I -TZ*<br />

eg oltfao ^crof ogfoo bortfofte z* og be ^eicre ^otcnfer af<br />

z, fan funne vi ffftte<br />

3fltfofl<br />

(i-Az=)-^= i-Az^4<br />

(i4-iz=)-*= i4-iz'^-j<br />

tg z ^:zz z . cos z ^<br />

Siffe gormler egne fig nu meget til Sogorit^me; Stegning;<br />

t^i vi ^ove ^erof<br />

log sin z log z -j- T l^og cos z<br />

log tg z := log z — ^ log cos z<br />

3(nvenbe vi bcm oltfon poo be ferfte ©robcr, foo fin;<br />

beg of 5ovlcrne let Cofinug ubcn ol Sntcrpolotion; z ber;<br />

imob jTol vffre ubtri;ft i Sele of Slnbiug; cr ben oltfoo gi;<br />

ven i ©ecunbcr, bivibereg meb 2o6264"8^ t^i fonmnnge<br />

©ccunbcr ^olber cn SBue ligcftor meb Slnbiug, of ^vilfct<br />

%a\ Sogorit^men cr 5,314425.<br />

©oolebeg finbe vi f. (Er. ©inug og 5ongeng of z<br />

= 2°i9'ii",7 = 835i"7 poo felgenbe 53ionbc:<br />

cos z = 9,999644 =: 0,000000 — 356<br />

cos z^ = 0,000000 — 119<br />

cos z ^ = 0,000000 -j- 237<br />

9)Ien<br />

logz = 3,921775<br />

— 5'3i4425 „,<br />

^- 8/607350


3(ltfao<br />

log sinz =: 8,607231<br />

log tgz z= 8,607587<br />

185<br />

^vilfc cnbog i bet fibftc Secimol cre olbdcg neiogtigc.<br />

©onlcbeg ville vi let for be ferfle ©rnber cvl^olbc Sogn;<br />

rit^mciSinuffevne og ^nngcntevnc, fom vi ellcvg, ubcn cn<br />

ufiffer og vibtleftig 3nterpolntion, og ubcn nt ubftvffffe Za;<br />

bcllcv i S5cgi;nbclfen mccv enb fibcn, ei funne cvljolbc.<br />

Silt. I. Omvenbt, f)vig vi ffulbe enten nf ©inuS<br />

ellcr 5nngcng finbe SBuen, ville vi ffftte<br />

sin z I<br />

sin z . cos z<br />

cos z'<br />

'0 '• . f<br />

z =: = sin z . cos z<br />

cos z •*<br />

f)Vor bn z for at finbe cos z blot bc^ever ot fjcnbcg om;<br />

trentligen, ibet vi ubcn ol 3i"terpolation toge of Sobdlcrne<br />

ben uffrmefte SSffrbie.<br />

Sill. 2. gor ot preve Steingtig^cbcn of biffe govm;<br />

Icr, ville vi ubflrffffe S5eregningen cfter bem inbtil 5". SSi<br />

^ave bo for<br />

©inug •^ongcng<br />

2<br />

3<br />

4<br />

5<br />

8,241855<br />

8,542819<br />

8,718800<br />

8,843584<br />

8,940296<br />

8,241921<br />

8,543084<br />

8,719396<br />

8,844644<br />

8,941951<br />

(Jnbnu vcb 5 ©rnber ofoigcr iffe 'Songenten i 6te Secimol<br />

nogcn fulb C'cn^eb.


186<br />

St Jim. gor at lette benne Slegning, fiat jeg t be ieo9«=<br />

rit5me:2.a»ler, fom af mig bliue ubgione, tilfeiet for:<br />

crcn veb Xalrgogarit^merne to Zal, S og T, fom iffe exe<br />

onbet enb ben Correction, SaUSogaritbnien faacr, for at<br />

ubtrnffe Sogaritbmen til ©inng og Xangcnten af et bcftcmt<br />

Slntal ©ccunbcr; ben conftonte ®i»ifor 2o6264"8, l)vi^<br />

Sogaritbme cr 5,314425, cr berimob ubelabt, ia benne<br />

let flebfe fan tilfeieg.<br />

§. 57. ©oolebeg ^nvc vi feet, ^votlebeg be lognrit^;<br />

mifTc og trigonometrifTe ©tarrdfer (gunctioner) labe ffg ub;<br />

trpffc veb Staffer, fom blive convergerenbe, og ^vorlebcg vi<br />

vore iftonb til veb bem ot ferfffrbige vore Sognrit^mc;'2a;<br />

fcctler fnnvcl for 'Jnllene fom for be trigonometriffe ©terrcl;<br />

fer. 3?ffften poo fomme 5)conbe Inbe olle ©terrelfcr i ben<br />

rene og onvenbte. S3iat^emotif fig ubvifle, og biffe Stffffcr<br />

blive bo ©runbloget for 'Jobellcrne, fom efter bem conftrue;<br />

vcg. Set vilbe imiblertib blive oltfor vibtleftigt, om vi fTulbe<br />

fcercgne olle Seeb, ^vorof en foabon 'Jabet, for ot ben funbe<br />

nicb Set^eb brugcg, mane beftnne. St 2(ntol, i gor^olb til<br />

felve 'Sovlett, i Tflminbdig^cb meget ringe, bercgneg ofteft<br />

ene ligefrcm, eg Steften, ber ligge imellem biffe, ubicbcg nt;<br />

ter nf f)ine. Sigclebeg f}ave vi unbertiben en 5nbel given,<br />

eller vel cnbog fung nogle Secb, ^vorof cn ^obcl fTal fot;<br />

fffrbigeg, til en vig og fterre Ubffrfffning cub ben, ber<br />

fro 93egi;nbdfen ^ovbeg; bo villc vi, of be og givne Sceb,<br />

ubcn ot venbe tilbngc til ben ?))ict^obe, ^vorveb be oprinbe;<br />

ligen ere funbne (noget, ber ofte enbogfoo iffe er eg muligt),<br />

ublebe olle Sebbene til ^obcllcn.<br />

Sen Stegniug, ^vorveb bette ffecr, falbcg 3"terpo;<br />

lotion, og fferc gormler lobe fig ubvifle, ^vorcftcr benne<br />

i be forffjcllige '^ilffflbc ^enfigtgmffgfigfl lober jig forctnge.


187<br />

gor flt ubtjifle cn olminbclig 3nterpolationg; gormel,<br />

villc vi nntnge, nt vi Ijnvbc<br />

y = A-j-Bx4-Cx--|-Dx'-j<br />

og bette y nf ben S&cffnffen^eb, ot for ct pnffcnbc x vilbe,<br />

i bet t)3iinbfte inben cn vig ©rffnbfe, bet vffre tilftrffffdigt,<br />

nt tnge nogle fnn Sceb (fov bet gevfte vilbe vi ene tnge be<br />

4 fvcmfnttc) for ot finbe y.<br />

SSi vifle nu ontnge at ^ove funbet oflerebe for fferc be;<br />

flcmte SSffrbier of x, ncmlig x, x„ x,„ be tilfvorenbe<br />

SSffrbier of j/ nemlig<br />

y, = A 4- Bx, 4- Cx,= 4- Dx,^<br />

y„ ^ A4-Bx„4-Cx„=4-Dx„'<br />

y,„ = A-j-Bx,„-l-Cx,„»-j-Dx„,^<br />

y.v = A4-Bx.,4-Cx,,= 4-Dx„'<br />

0. f V.<br />

SSi inbfee nu, at vore A, B, C, D cnbog iffe givne,<br />

eflcr fjenbte vi albcleg iffe Stffffcng S^otur, vilbe vi bog funne<br />

nf be befjcnbte y, y„ finbe bem, bo be cre og givne<br />

veb Sgqvotioncr of ferfte ©rob.<br />

gor beqvemt ot finbe ben, toge vi:<br />

y„-y, = B(x„-x,)4.C(x„^-x,=) + D(x„3-x,3)<br />

^Bovaf lober ffg bonne<br />

y'dy' ^ B4-C^^^^--::4-D"^^^::1-"-:!<br />

= B4-(x„4-x,)C-j-(x„»4-x„x,4-x,=)D<br />

Senne ©terrelf'e ville vi betegne meb B, og ligelebeg ffftte<br />

2S„ = B 4- (K,„ 4- x„) C 4- (x,„» -j- x,„ x„ 4- x„=)<br />

»,„ = B4-(x„H-x„)C-|-(x,/4-x'x,„if x,„=)<br />

jjcvaf ublebe vi otter<br />

h,,—:^, = (x,„—x,)C4-(x,„='4-(x„, —x,)x„ —-„=)D


188<br />

eg veb ot bivibcre meb x„, — x,<br />

= c4-(x,„4-^--f x,)D<br />

X/// ~~- X^<br />

I)vilfen ©terrdfe vi ville betegne meb C, og ligclcbeS<br />


189<br />

og inbffftte vi ntter D = JD, bo fiove vi ben olminbdige<br />

3nterpolationg; gormd<br />

y = y, 4 (X - X,) [1^, + (X - x„) (C, + (x - x,,,) jD,)]<br />

.fjovbe vi taget fferc Clcmentcr cub y, 23, C, JD, for at<br />

beftemme y, vor gormlen blcven olbcleg ligcovtet meb ben<br />

fremfntte.<br />

Set bliver ftebfe ^cnfigtgtuffgfigft nt tnge x—x,; x —x„<br />

fno fmane fom muligt; berfor vfflge vi imeflem be eg<br />

givne ©terrelfcr i 3(lminbclig^eb fnnlebeg, nt x, fnlbcg ben,<br />

bcr ligger x nffvmcfl, x„ ben berpnn nffrmeffe, o.f v.<br />

X og ligdcbcg x, x„ fnlbcg 5(rgumcntec<br />

fee y y, y,/<br />

2( n m. ©om eiempcl oiHe vi tage folgenbc<br />

Log 1931 = 7,5657932824<br />

Zo^ 1938 = 7,5694117925<br />

Log 1940 = 7,5704432521<br />

Zo^-^ 1946 = 7/5735312627<br />

eg beraf intcrpolere 1937; oi oitle ba f«tte<br />

x,==i938; x„ = i94o; x„, = 1931; x,y = i945<br />

Sa er<br />

», = 5157298,0 C, = —1333'6<br />

X)„ = 5166633,0 5D, = 4-0,46<br />


190<br />

§. 58» Snterpolfitionert IctteS 6eti;beligt, ^vig vi ^ave<br />

flere Sceb givne, ber fvnrebe til 3trgumentcr, fom ffrebe frem<br />

i nrit^metiff ^progrcgpon; Siffcrentfen i benne villc vi nntage<br />

fom Sen^eb, eg bo ffftte for bet Seeb, vi ffulle fege,.<br />

X = X, -j- m<br />

f)Vor X bo gjfflbcr for bet nffrmeft foregooenbe Sceb, og m<br />

er en egentlig ?£>xef. ©om y„ tnge vi bet Seeb, bcr felgcr<br />

pnn y,; fom y,„ bet, ber gooer foron for y,; og fom y,^<br />

bet, bcr felgcr pao y„. 31'rgumenterne, fom oltfoo gaac<br />

frem i orit^metifT proportion, meb bcreg Secb, ftooe foolebeg<br />

x„,<br />

X,<br />

x„<br />

X,y<br />

J"^<br />

Dy„<br />

Y' D.y,<br />

Dy/ D,<br />

7" D.y/,<br />

Dy///<br />

y.v<br />

Dy, Dy„ ere be ferfte Siffcrentfer, fao ot<br />

^j' = J" — y' ^y" = 7' — Y"' 0- f-«.<br />

ligelebeg er D^y, D^y,, 2{nben; Sifferentfcrne ellcr<br />

D^y, = Dy, — Dy„ D,y„ = Dy,„ — Dy„ 0. f V.<br />

frembdeg Srebie;Sifferentfcrne D3y, D^j,, foo ot<br />

D3y, = D,y„—D,y, o.f v.<br />

2ff biffe Siffcrentfer lobe nu let Slementerne 35, B,,—-<br />

C, C, ©, 0. f V. ffg bonne poo felgenbe S3?aob«<br />

x„ — X, =4-1 X,/, — X, = — 1<br />

I/// —X„ = — 2<br />

X,v — X,„ =4-3<br />

aitfoft<br />

•X, = — 1<br />

• x„ = 4-1<br />

X,y X/ =4-2


191<br />

y,„-y„ -(Dy„ + Dy,)<br />

»„ = —r- = :; = KDy//-{-Dy,)<br />

»,„ = '-^;- = J_LZX2_ = . (Dy„+Dy,+Dy„,)<br />

Jjcraf attcr<br />

X,„ — X, — I - '^'<br />

gor ot banne (t„ tage vi<br />

„ „ _Dy„,4-Dy//-fDy/ Dy„4-Dy,<br />

3 2<br />

i(2Dy„,-Dy„-Dy,) = KD,y//4-D,y,) + iD,y„<br />

= iD,y„+iD,y,<br />

oltfoo, bo x,y — x„ = -{-I, cr<br />

€„ = iD,y„-j-|-D,y,<br />

2tltfaa<br />

__ ^z:^ __ ^(D^y/, —D.y,)<br />

' X,^, —X, 2<br />

= iD3y,<br />

So nu X ^ X,-j-m, foo et<br />

X — X, = : m<br />

X — x„ =: m — I<br />

X — x„, = m -j-1<br />

3tltfao<br />

y = y/ + m[Dy,4.(m-i)[iD,y, + (m + i)iD3y,]]<br />

So vi poo fomme S3ioabe funne ublebe be felgenbe<br />

eiemcntec, vifle vi inbfee ot ben olminbdige Snterpolotiong*<br />

gormel for Jtrgumcnter i lige Jlfffnnb er


192<br />

y = y<br />

4-111 JO„+^T:1[D,,+=±;(.,„+==2(O..-))]|<br />

Slntit. ©om Crempel ville vi tage Sogaritt)mc:2;angen:<br />

tetne af 13°, 14-, 15°, 16°, 17°, 18°; beraf inteipo:<br />

Icre 15° 24'<br />

+<br />

13= 9/363364 —<br />

33407 4-<br />

14 9,396771 2125 —<br />

31281 288 4-<br />

15 9,428052 1837 52<br />

29444 236 ]£<br />

16 9/457496 1601 41<br />

27843 195<br />

17 9/485339 1406<br />

•26437<br />

18 9/5II776<br />

m = -=i = f, altfaa<br />

m = -j- 0,4<br />

m — I :^=. — 0,6<br />

m-j- I = 4- 1,4<br />

in — 2 = — 1,6<br />

m-j-2 ^=z 4" 2,4<br />

Se unberflrcgcbe Siffcrentfer ere be, fom onvenbeg. Sicg;<br />

ningcn fereg nu faalebeg<br />

m-j- 2<br />

D,y, rcttcs mob D^y,<br />

5<br />

m — 2<br />

®ctte tageg Oangc og anbringeg til D3y,, Ijcraf<br />

4<br />

m-j-i ^ m — I<br />

tageg otter , l;«ormcb D^y, retteg, beraf ,<br />

3 2<br />

I)»ormeb Dy, retteg, og cnbeligt anbringeg bette muls<br />

tipliccret meb m til y,; faalebeg fjAWi, l)»ig open;<br />

flaaenbe S^al onvenbeg,


193<br />

log tg 15" 24' = 9/400036.<br />

gelgcnbc !Bem«vfning vil lette £)pm«r(fomf;cbeH pa«<br />

Segnct af Siffeventfevne: So m —i, m —2 K. ffebfe<br />

ere ncgntirc, faa inEi|\'eg: at, [)»ig be lige Siffcrentfer,<br />

anben, fjcrbe :c., Ijauc famme Segn fom be uligc, forjlc,<br />

treble, fcmte ic, ba Hive biifc bcrueb forminbffcbe, bete<br />

imob be lige Siffercntfer fovmerebe veb be nligc, faae<br />

fremt Segnct er bet fammc (benne gormevelfe diet govt<br />

jninbffdfe tageg alffolnt, l)vai enten ©terrelfernc ere<br />

pofitioc cller ncgatioe, faa at vt talbe gormevelfe, at<br />

be feniine til at tcftiiae of et flerve aintal eutcn pol'irii'C<br />

eHer negatioe eenl)ebev), omocnbt berimob, l;oig Xegnet<br />

cr mobfat. SKcn, ba enl;»er np Sifferentg = 9;(¥:'fe faaer<br />

fammc Segn fcm ben fovegaacnbe, forubfat at benne ct<br />

obfolut tiltagcnbe, faa inbfeeg, at i ben ferfle, trebie,<br />

femte ... SiffcvcntgiSJIaEEe ben Sifferentg, ber bruges,<br />

flebfe veb gorrectionen of anben, fjcrbe, fjctte... Siffci<br />

rentg-. 9ia!!fc, bringeg ben ooenflaacnbe Sifferentg wxi^<br />

mere; berimob i anben, fjcrbe, ffctte ... Siffcrcntgc<br />

3ioeEtc bringeg ben brugte Sifferentg oeb gcrrectiencn ben<br />

eftevfelgcnbe notvmcvc; faalebeg i bet fremfatte gtempcl<br />

blioer 52 fcrminbffct, 236 foimerct 0, f B.<br />

§. 59. Cnbnu fnoer 3ntcrpolationg;gormlcn cn nnben<br />

©fiffclfe; nnnr vi ffufle intcrpolere mibt imellem to Sceb<br />

of en Stffffe, bo cr m = i, felgdigcn<br />

altfao<br />

y = y'<br />

m = i m-f- I = T<br />

m — I = — i m — 3 = — J<br />

+^(Dy/-i (D.y/4-^ (D3y, - i (D, V,-f • (D.y, --))))<br />

~ Y ' + ^Dy, -i.i(D,y, 4-iDjy,)<br />

+ ^.i:.l.i(D,y,4--J:D,y,)<br />

Cflcr, bo y,-j-^Dy, = 4(y,4-y„), fao funne vi<br />

inbffftte benne ©terrdfe, fom vi vifle fnlbe-i-A, iffebctfot<br />

y,4-4-Dy,; ligelebeg betegne vi ^^Y'-^-i^yY' ==<br />

T(D2y/4-D2y„) meb ^B, o.f v., eflcr vi ffftte<br />

II. 13


194<br />

Y' + Y" = A<br />

D,y,-hD,y„ = B<br />

D,y,-KD,y„ = C<br />

0. f V.<br />

oltfoo er<br />

„ 1 A 1 I t TJ I 1 I 1 s 1 p<br />

y ^r t\ T . T • ^J J-* T^ T . T . T • T . TT ^<br />

J- . i . V . ' . -- . ' D -I<br />

^ |A-i[B-A(C-A(D-A(E—)))]j<br />

SMtiin. ®cm Crcmpel vtere given felgenbe:<br />

Sfelge en ©ebeligljcbgr^abel of Suvillarb, ffet;<br />

tet paa ascregningcn of Sebcligljeben t gronfrig for<br />

loooooo 9ci)f«bte, bar jeg beffemt Sivctg aJlibbcU<br />

sgarigbcb eflcr 2Ribbcltallct of be 3lntal Slar, en spcr-fon<br />

of en beffemt 2llber ^ar at Icve, for felgenbe Sllbrc;<br />

ailber<br />

4<br />

12<br />

43/26 —<br />

3,83<br />

39,43 -1,34<br />

20<br />

5,17 4-1/89<br />

34/26 +0,55 —2,30<br />

4,62 —0,41 -j-2,5i<br />

28 29,64 -{-0,14 4-0/2I —2,41<br />

36<br />

4,48 —0,20<br />

25,16 —0,06<br />

4-0'io<br />

0,31 0,25<br />

4/54 4-0/" —0,15<br />

44 20,63 -1-0,05 -l-o,i6 —0,03<br />

52<br />

4/49<br />

16,13 0,32<br />

0,27 +0,18<br />

—0,02 4-0/19<br />

60<br />

4,17<br />

11,96<br />

4-0'25 4-0/01<br />

0,57 —0,01<br />

68<br />

76<br />

3,60 4-0/24<br />

8,36 4-0/8I<br />

2/79<br />

5/57<br />

Sntcrpolcre vi l)cr, for be mellemliggcnbc 2lar 32, 40,<br />

48, ctftolbe vi, l;oor uregclmagfige enb Sifferentfcrne<br />

fiDneg at vojre, SSccrbicrnc 27,41; 22,90; 18,35; f'"'


itte afoigc fva be oirfdigen umibbelbart beregnebe. ^1'i<br />

Ijave faalebeg f»lgenbe label;<br />

28<br />

32<br />

29,64<br />

2,23<br />

27,41 —2<br />

36 5,16 I<br />

40 2,Q0<br />

2,26<br />

— 2<br />

1 2,2,S<br />

44 j 20, A 2 -j- r<br />

48 ' if^'35 4-5<br />

I 2,22<br />

52 I 16,13<br />

f)vct Sifferentfcrne allcrcbe eve mevc vegelmagfige. Se<br />

betpbdige ©pring, bcr oarc i Siffeventfevne i fevfte<br />

5S0!!fc, l)ibr«rc bcctg fva ©jenflanbcng 58effnffenl)eb, bcelg<br />

fra ben Ufitlerbeb, bcv ilcbfe finbeg i fibfle Sccimal.<br />

3 gvemplct ere Siffcrentferncg Segn tilf»icbe; »i funne<br />

eDerg let paa f«lgenbc 5D?aabc l)a»e taget .^cnfpn til bcm.<br />

SScnotone oi be 4 paa l;inanben felgenbe Secb i giaiffcn<br />

meb ]\], N, P, Q, faa er ifle Siffcrcntg=3iO!Ete J\ —j\l;<br />

P-K; Q-P;2bcn Siffcrentg=Oi«tte P-2N-}-]\1;<br />

Q —2P + JN; ©ummen af SMubeu^Siffercntferne Q-|-M<br />

— (N+P). & ©ummen af be metfemfce Sceb, ]N eg P,<br />

imellem 0»ilfe interpolereg, altfaa minbre enb af be vbet:<br />

ffe (nogct ber oeb et let Docrflng fnavt fccg), ba blioe<br />

N, P, cftcrfom Sifferentfcrne ere pDlitioc, forminbffcbe,<br />

ellerg formcrebe; ligelebeg ainbcn-.Sifferentfcrne, forme:<br />

bclff gjcrbc: Sifferentfcrne, 0. f v.<br />

§. 60. 3fflercbe ovenfor (I. §. 55) er gorflaringcn nf<br />

^jffbebreff given. S3igtigt}cben og 3lnvcnbelfen of bem<br />

til at forforte ofte cnbog olbdcg ffmple Stcgninger, fi,mteg<br />

tilflrffffeligen ot ^jemlc bcm ^Inbg i ben demcntffrc 'iixitf)i<br />

mctif *). SScb Jpjfflp of S5ogffov;Stegningen vifle vi imibler;<br />

*) 3fOEt cre vi Bcb ^jceiic«'8tof ijlani) tit at iit)tti)ffc ct gotf)OIb noa<br />

let SJoEtmcjie meb minbre f)Cte Sat. 3iaat gortjolbcts gimie i«b


196<br />

tib Vffre iffonb til f)cr fulbffffnbigcn ot be^onlte tern, og ub;<br />

(trffffe bereg 5(nvcnbelfe til ffere of be ffben fremfntte ©tet;<br />

rclfec, fom vi ^nvc ubtn;ft veb Stcffer.<br />

Sen ovenfor (I. §. 55) beffnerebe ^jffbebref ^ottbe<br />

felgenbe nlminbdige ©fiffclfe:<br />

I<br />

I<br />

a-\ I<br />

b4- J<br />

d4----j<br />

j^crof vare 'Portiol; SBr^ferne<br />

a<br />

I b<br />

^^rjii--^"^<br />

b<br />

f JC.<br />

1 be 4-I<br />

3 ) a — 4- I -— I — abc 4- a 4- c<br />

^+r<br />

I bcd4-b4-d<br />

^•^ 7+ ^ I abcd + ab4.ad+cd4i<br />

b4---i<br />

e. f V.<br />

itfc f)a\ie nogcn abfctiit SJeiagtig^cb, citcc og oi ingcn faaban fraiie,<br />

6il SRcgningcn 6eti)betigcn IctteS neb at tage tcenct 09 9iaviiict af tn<br />

spartial.^rot tit Secb i ct gotOotb, fom ba jiaa bet SfiOEVuiciic ubtrijtfer<br />

tet giune got^olb. Slnbtc ainocnbetfcr ^anc oi feet I. '*il^m.<br />

{. 74. Sin. 3. 09 I. ©com. j. 149.


197<br />

Sn^ver ni; ^ortlflI;95ref lober (Ig let bonne of be funbne<br />

pno felgenbe Slioobe. SSi multiplicere ben ffbffc ^ortial;95reif«<br />

Sfffler meb bet ^de Zal, ber fvorer til ben


198<br />

Sill. I. SSifle vi beffemme gorfFjellen imellem ben<br />

nte og ben (n —i)te ^nrtinl;5Bref; fnn, ^vig vi betegne<br />

N M<br />

biffe meb i^: "9 i^T' ^^" ^^^ Clvotient meb n, eg, bo<br />

l)VOC<br />

N<br />

rs^ '<br />

L<br />

^- betcgner ben<br />

i\ M<br />

N^~ "i\!'<br />

Mn -J- L<br />

M'n-|-L'<br />

(n — 2)bc sportiol ;a5re'f. er<br />

,\M/ _ MN'<br />

N'M' ~<br />

(Mn -f- L) M' — M (M'n 4-L').<br />

K'.M'<br />

LM' — L'M<br />

K'M'<br />

So M, M' ^ere ben (n —i)te 'PnrtioliSSref til, foo,<br />

^vig vi ffftte<br />

M Lm4-K_<br />

M^ L'm4-K/<br />

f)vor K og K' cre ^ffUer og 3?ffvner i ben (n — 3)bc 'Par;<br />

tinL'sSvuf, m ben (n — i)te O.voticnt, er<br />

OI' —L'M<br />

= L (L'm -f- K') — L' (Lm -j- K)<br />

= LK' —L'K<br />

SSi ville nitfnn ligefnnvel funne ubtri;ffe Sffflev i ben SSref,<br />

ber ubgjer govffjellen mdlcm ben nte og (n — i)te 'Pnrtinl;<br />

?&r0f, veb 'Jffflec og S^ffvner of bcu (n— i) og (n — 2)te<br />

'PnvtinI 33v,0f o. f v., eflcr olminbcligt of l)vilfefoml)dff umibbd;<br />

bnvt pan l)iunnben felgenbe *Pflrtial;$5v«fer. 2age vi oltfoa<br />

ben ferfte og nnben, fno ^nve vt<br />

Oib'4-j) X I—ab = I


199<br />

3lltfan cr ?ffflercn ffebfe i; men, bo LM' — L'M = K'L<br />

— KL'=r —(KL' —K'L), foo ^or KL' —LK' et mob;<br />

fnt 5cgn nf LM' — L'M, ellcr cr benne + i, fnn cr fjiin<br />

+ I; felgdigcn ere gorjTjeflcne nfvcrlcnbe pofitive og negn;<br />

tive, og gorffjeflen imeflem 2ben og iffe 'Pnrtinl;S&ref ec<br />

negntiv, imeflem 3bie og 2bcn pofttiv o. f v.<br />

Sill. 2. ©ubtrn^ereg cn ^Pnvtinl; SBref frn .^oveb;<br />

ajrefen, bo lober benne gorfFjd jtg olminbcligt ubtn;ffc.<br />

N<br />

ajetcgne vi fom for^cn ben ntc ^ortiol; .QSref meb r- =<br />

Mn4-L<br />

„^ ,\-f fan lob J?ovcb;.Q5refen (ig ubtri;ffe vcb blot ot<br />

ffftte iftebctfor n, cfler bet ^cle Zal, ben fulbflffnbige Clvo;<br />

tient, fom blev, noor ben tilfvorenbe Stcft vor r, og Si;<br />

r<br />

vtfor eflcr ben nffftforcgoncnbc Stcft R, inlt n-J--; oltfno<br />

R'<br />

vor J?oveb;93r0feii, fom vi vifle betegne meb<br />

15<br />

M(\V + £) + L<br />

M'(n-h04-L'<br />

NR4-Mr<br />

(Mn-f-L)R-l-Mr<br />

(M'n4-L')R4-M^<br />

— N'R4-M'r<br />

Stage vi nu J5oveb;23refen fro ^nrtiol; SSrefen, fao er<br />

r^ 13 N NR4-Mr<br />

K'~~^ N^~W^-fM^<br />

NN'R -j- NM'r — (NN'R 4- N'Mr)<br />

N' (N'R 4- M'r)<br />

(NM' —N'M)r<br />

N' (N'R -j- M'r)


200<br />

'SKen ISM' — N'M er ligefom otic Siffcrentfer bnnnebe paa<br />

lignenbe S}?aobe + i, nltfoo er gorfTjcllcn, ^vig vi tillige<br />

ffftte N'R-f M'r = 13',<br />

±r<br />

N' iij'<br />

Sn nu r ftebfe oftnger, N' tiltoger, foo nffvme fpnt;<br />

ttal;SJ>rofcvtie ftg ftebfe mere eg nlere ijoveb; SSrefen, 09,<br />

bn Sijferentfen ^nr Scgnct ±, fno inbfeeg, nt 'Pnvtinl;<br />

S&v0ferne ofvcrlcnbe ere (tKre og minbre enb Jpoveb^Srefen,<br />

nemlig ben fevfte ftjrre, ben onbcti minbre, ben trebie nt;<br />

ter (tetre 0. f v.<br />

Zill- 3. .^oveb;S5ri>feti ligger fnnlebeg (tebfe imellem<br />

to pno f»inonben felgenbe *Pnrtinl;S5refcr, og gorffjeflen<br />

imeflem biffe overgnncr oltfno ftebfe gorffjeflen fro ipovcb;<br />

Srefen, foo ot vi veb benne, ber let finbeg C^ifl. i), funne<br />

ftebfe gjere et Ovcrflag over ben geil, vi bcgooe, vcb ot<br />

toge en J?oveb;S5r0f iftebct for en ^ortiot; SSref.<br />

Sill. 4. ^ovbe vi en ucgcntlig .^jffbe;23r«f (I. §. 55.<br />

?ifl,), bo lob poo benne (tg olbdcg onvcnbe bet gremfotte.<br />

3(ntn. ©em erempler pa« ^jajbebr^f 09 bereg partial*<br />

ajrvfcr tjcne felgenbe:<br />

1)1^'-?<br />

5537<br />

^-(•vctageg §er felgenbe SioifiJn<br />

I769i5537<br />

1610.5307<br />

159! 230<br />

1421 159<br />

171 71<br />

15I 68<br />

2 3<br />

2 a<br />

o I


®aa cre jQooticntcrne<br />

3, 7, I, 2, 4, 5, I, 2,<br />

Oicflcrne<br />

230/ 159' 71/ 17/ 3/ 2/ I, o.<br />

Slltfaa ..^jcebcbreCcu<br />

7-h—I<br />

i-f—I<br />

2-h— I<br />

4-f I<br />

5 + —I<br />

Spartial^Svefernc bleve<br />

_i_ ^ 8 23 100 523 623<br />

3' 22' 25' 72' 313' 1637' 1950<br />

gcvfljcUcne fra ^oocbbrefcn<br />

, 230 230<br />

3X5537 — "T": 16611<br />

159 159<br />

22X5537 121814<br />

71 , 7i<br />

25X5537<br />

17<br />

138425<br />

17<br />

72X5537 396644<br />

3 I 3<br />

313X5537 — "t": 1733081<br />

1637 X 5537 9064069<br />

I . I<br />

1950 X 5537 10797150<br />

3<br />

201<br />

II) 3- ^ 3/1415926536<br />

So benne SecimolbreC ec ofbrubt, fao, ^oig vi ^avbe,<br />

efter bc« fajboanlije Diegel (I. 5. 35. EiB. 2), bcflemt


202<br />

bet fibfle eiffer, var ben mulige geil cnbnu + 0,49999betegne<br />

rt altfaa benne meb x, fao er<br />

14159265364-X<br />

TT = 3-<br />

I0000000000<br />

I)»or X ligger imeflem -j- Ms — 1 gorctagfg nu Sis<br />

vifionen, ba flaacr ben faalebeg;<br />

1415926536 +<br />

13^7713720 +<br />

882I28I6<br />

602864<br />

2792641<br />

2712888<br />

797536<br />

602864<br />

X<br />

105 X<br />

4- io6x<br />

+ 32996X<br />

1946724-33102 X<br />

106760 + 332I5X<br />

I0000000000<br />

9911485752 ±7X<br />

88514248 —7 X<br />

88212816 + io6x<br />

301432 —113X<br />

194672 + 33102X<br />

106760— 33215X<br />

87912 i 66317X<br />

18848 —99532 X<br />

87912 4-66317X<br />

3nbf«tte vi nu x =:= iJ-, faa inbfee vi at ben fib|le<br />

(Kcfl liggcr imeflem —30918 og 4-68614.<br />

sjKeb benne 9iefl, fom faalebeg er albeleg ubeitcmt,<br />

^j«lpcr bet iffe at fortfojttc Sivift'onen; vi t)ere bcgaar^<br />

fag i ailminbcligOeb veb Sccimal:S8ref op, faafnart x'g<br />

Coefficient bliuer fterre enb Oieiten.<br />

be funbne iivoticnter, faa ere biffe<br />

^agc vi altfaa ene<br />

3, 7, 15, I, 292, 1,1,1<br />

3 cr bet fevfte l)ele 3;al, og Sjojbebretcn bliver beit, bet<br />

for 3- cr frcmfat (I. ©corn, §. 150).<br />

fevnc eve<br />

spartiaUSve:<br />

„<br />

3/<br />

22 ill 3 S S<br />

T/ TTli./ TTT/<br />

] 03 99 3<br />

TTToT /<br />

1 0 4 3 4 S<br />

TTTTT /<br />

2 0 )i 3 4 1<br />

6 6 3 n /<br />

313189<br />

UlsTT*<br />

gor nu at bcftcmme ©roenbfen af be geil, vi bcgaae<br />

veb at tage en spartialrSBref iftebct for r, vifle »i bvage<br />

be paa Ijinanbcn felgenbe ^partial = SSrefer fra liinanben<br />

(Zill. 3), D« finbe faalebeg, Ijoig vi fojtte ^ =<br />

3, gcilcn minbre enb V —3<br />

2 2<br />

T<br />

33^3<br />

1 oT<br />

3 S S<br />

J03 993<br />

TTTOTT<br />

0. f V.<br />

1 i ><br />

TTT<br />

3 5 5<br />

3)3<br />

10 6<br />

3 3 3<br />

LOW<br />

10 3 9 93<br />

TTToJ"<br />

J 03 9 9 3<br />

33 ioJ<br />

1<br />

T<br />

TTToTTS<br />

i


203<br />

9?eb af biffe ipartial=3?refcr at tage ben fibfle WTW<br />

eg fcroanblc ben til Sccimal :5Bvet, cvl;olbe oi<br />

3,1415926536<br />

altfaa n- neic faalebeg, fom oi tjaue anrcnbt ben, for<br />

bcvaf at finbe ^iabe:58vo{en, faa at oi Ijarc ogfaa bcr<br />

cn ipreoe, at Sioifionen oar tilflrceEEcligen fortfat,<br />

§. 61. S?i funne ^ove fammcnljffngcnbc SErefer of en<br />

nlmlnbcligcre ©fiffclfe, enb ben bcfinercbe .^jffbebvef, ^vori<br />

5ffflcrue ftebfe vore i, f. Sr.<br />

a<br />

a-l c<br />

c-j--—<br />

^ +<br />

(£n fanbnn vnr ben, vi ^nve fvemfnt veb a.vnbrnt;<br />

ertrnctionen (I. §. 74. 5ifl. 3).<br />

Ogfnn nf en S&ref of ovenftancnbe nlminbdige ©fiffclfe<br />

Inbe fig Q)artifll;93refcr ubvifle, fom bleve<br />

a<br />

I)- a ttb<br />

^^ abc-j-ca-j-cb<br />

abed -|- acd -j- abh<br />

^^ ^d -j- cad -jTbcd+Tab -j- hb "' ^' ^'*<br />

?;ngeg govfTjcflcnc imeflem to pnn l)innnbcn felgenbe 'Pnvtinl;<br />

a^vefer, bn cre biffe<br />

^'' — ^^ a(ab4-b)<br />

— abc<br />

^^~ 3) = (^b+l-Kabc-j-ca-j-bc) "' ^*"*


204<br />

aSi inbfee, nt biffe Siffcrentfer vifle i ^fftlercn cr^olbe<br />

efter^oonbcn 55ogflavcrne ab, abc, abc6 o.f v., og fUm<br />

nercn blive ^robuctet of be to 'Partial; SSraferg 3'Jffvnere,<br />

^vig Sifferentg ffufle ubtri;ffeg. $5vugc vi o!tfnn fnmme<br />

S&etegnelfeg;S)iocbe fom for^cn (§. 60. '5iU. 3), ncmlig ffftte<br />

i(te Q>ortiol;95r«f liig<br />

2bcn -<br />

3bie -<br />

A'<br />

£<br />

0. f V.<br />

foo ere gor(rjeDene<br />

ab «bc abcb<br />

^A'B'<br />

og ligelebeg<br />

B'C' ' CD'<br />

M N abc-<br />

M' iX' — M'N'<br />

Omvenbt funne vi oltfoo ffftte<br />

N M_abc n<br />

3lltfoa<br />

W' M^ "^ ~mW~<br />

M<br />

M^<br />

L<br />

±<br />

abc<br />

L'M'<br />

N L abc tit abc - -<br />

N^ 1/ + "^"L^M'" + ~M^<br />

L K<br />

Ubtri;ffe vi nu — otter veb ^jfflp of ^7- og gov(TjcI;<br />

L' Jv'<br />

lett; benne ^ortiaI;25r«f otter vcb ben foregooenbe, og frem;<br />

belcg til vi fom til ben ferfte 'Pnrtinl;S3re'f, foo vor<br />

tn


205<br />

N A rtb . «bc<br />

N' A' A'B' ' B'C'<br />

M N<br />

aSor ^- oflerebe ben fibjte 'Partial ;S5ref, fno vor =^<br />

A a<br />

.^ovcobrefen, tiflige cr — = —; oltfao, ^vig vi betegne<br />

I\. Si<br />

ijovcbbr^fcn fom fov^en, foo cr<br />

13 tt ab . abc<br />

13' a A'B' ' B'C' ^<br />

Silt. I. ©dv om ingen "PovtinhSSref funbe folbeS<br />

ben fibfle, ibet ben fommcn^ffitgcnbe aSref blev uenbelig,<br />

vilbe bog JjovcbbrMen lobe (tg ubvifle, men i en uenbelig<br />

Stffffe of ovenflonenbe gorm, iftebct for, ot, noor ben<br />

fommen^ffngcnbe 55ref vor (luttet, blcv Stffffcn bet ogfoo.<br />

S t n. 2. Sen af ben fommen^ffngenbe 93r0f funbne<br />

Stffffe ^cvbc ofvcrlcnbe 'Jcgn: jpovbe oflc ©terrelfernc a, b,<br />

c, b Vffret negative, fno vilbe ben tilfvnrenbe Stffffe<br />

^ove vffvct negativ. J?nvbe vi nitfno tngct cn foobon ^xeS<br />

fdv negativ, vor cn Stffffe meb lutter pofitive Seeb opftooen.<br />

§. 62. ©fulbe vi omvenbt ^ove foronbret en given<br />

Stffffe til en fommen^ffugenbe S&ref, bn ^nvbe bet vffret<br />

muligt, vcb ot fammenltgne Cebbcne meb ben (§. 61) funbne<br />

Stffffe. 2i


206<br />

^vilfen vi for ^ort^ebg ©fijlb, bo ben of^ffnger of be 4<br />

Slemcnter p, q, r, x, vifle betegne meb F (p, q, r, x).<br />

SOtcb i?cnfi;n til p og q cr Stffffcn olbcleg fommetcijT,<br />

foo nt vi funne forvcrle biffe 93ogftnvcr, eflcr ffftte<br />

F (p, q, r, x) = F (q, p, r, x).<br />

Snnne vi en nlbcleg lignenbe Stffffe of Slemcntcrne<br />

p, q-J-i-' I'-f-i' ^f f""" ^' ''•'•c betegne meb<br />

F(p, q-f-i/ r-f-i/ x), foo cr benne<br />

, pCq-HO ^ • p(p-^I)Cq-^I)(q4-2) ^,<br />

^"^1.(1-4-1)'' I- 2 (r4-i) (r4-2)''<br />

p(p-


F (p, q, V, x)<br />

F (p, q-j-i, v-f-i, x)<br />

p(r — q) F(p-j-i- q4-i/ i'4-'-/ ^)<br />

r (r -j- i) F (p, q 4- I , r 4- I, \)<br />

.^oovaf nitfnn vil felge<br />

F (p, q, r, x)<br />

207<br />

F (p/ q 4- I / 1- 4- I' 5^)<br />

P(r —q) F (p4-i, q-j-t/ i'4-2^ x)<br />

r(r-j-i)^ F (p, q-j-i, 1 + 1, x)<br />

3lltfao omvenbt<br />

F(p, q-j-i, i'4-i/ x)<br />

F (p, q, r, x)<br />

I<br />

P (!• — q) F (p-j-l, q-j-i, 1-4-2, x)<br />

r(r4-i) F (p, q4-i, r-j-i, x)<br />

gor ot ubvifle Clvotientcn i Stffvnevcn of bette f&xeh<br />

Ubtvyf, be^Bve vi blot ot beraffrfe, ot p og q funne em;<br />

bijtteg, nltfao vifle vi funne finbe bet neie paa fnmme CiKnobe<br />

fom bet funbne, eflcr og be^eve vi blot ^eri ot ffrive q-j-i<br />

iftebct for p, p for q, r-j- I for r, altfnn er<br />

F (q-f-i/ p-fi/ i'-j-2, x)<br />

F (q-|-i/ p/ r4-i/ x)<br />

I<br />

(q-t-i)O--l-i—P) F(p4-i, q-j-2,r-j-3,x)<br />

(r-j-i)(r4-2) F(p4-i,q4-i,r + 2,x)<br />

.ijvor vi bn otter vifle vffre iftonb til ot ubvifle Clvotientett<br />

paa famme iSioabc. SScb bo frembdeg ftebfe at ubvifle ben,<br />

inbfee vi, ot vi cv^olbe en ^jffbebvef af felgenbe gorm:


^voc<br />

208<br />

JC F (p^ q4-i/ r-j-1, x)<br />

ax F (p, q, r, x)<br />

bx<br />

ex<br />

0. f V.<br />

P (r — q) , Cq-f-i)(r + i—p)<br />

* — q(r4-i) (r4-i)(r4-2)<br />

(p4-i)(i-4-i —q) , (q4-2)(r-j-2—p)<br />

= — (i.4_2)(r4-3) — (r4-3)(r-j-4)<br />

(p-j-2)(r4-2 —q) __ (q4-3)(i--f 3 —p)<br />

* (;r4-4)(v4-5) (i- + 5)(r4-6)<br />

0. f V.<br />

Silf. Ovenftoocnbe ^jffbebref ubtri;ffcr Q.voticntett<br />

nf to Stffffcr. ©fftte vi q = o, bn bliver F (p, q, r, x)<br />

1; vi er^olbe oltfoo i bette 'Silffflbc cn Ubvifling of en<br />

enfelt Stffffe, ^vcri vi enbnu vifle ffftte, iftebctfor r, r —i,<br />

bo cc<br />

F (p, I, r, X) = i4-P-x4-^P4r^''' +<br />

vr' ' ' ' ' r q (r -j-1)<br />

^voc<br />

ax<br />

I bx<br />

cx<br />

dx<br />

I •<br />

ex<br />

a = -5- b = ''~P<br />

r r(r4-i)<br />

I


209<br />

c ::== (P+Qr j 2 (r -j- I — p)<br />

'' — (r-hi) (1-4-2) ' ""(1-4-2) (V 4-3)<br />

c =: (p4-2)(t- H;^Ji) ^ 3 (»• 4- 2 — p)<br />

(r 4-3) (1-4-4) (i-4-4)(i-4-5)<br />

§. 63. 3tnvcnbclfcn of ovenflnncnbe gormler fan let<br />

gjercg pan forfFjeflige Stffffcr.<br />

5age vi SMnomial; gormlen (§. 45) og ffftte beri<br />

(a4-b)'> = an^i-l--^<br />

b<br />

09 enbvibere — = u, foo Inbcr (i -j-u)" =<br />

a<br />

, n(n—I) n(n —i)(n —2)<br />

I 4- nu -j u- -{ u^<br />

' I. 2 I. 2. 3<br />

(tg fnmmcnligne meb ben fibfle Stffffe, nnnr vi nemlig ffftte<br />

F (p, I, q, x) = F (—n, I, I, —u)<br />

bn fnnlebeg<br />

fno er<br />

a =<br />

c =<br />

(I 4- U)n =<br />

n<br />

I<br />

(n-i)<br />

2- 3<br />

2 (n — 2)<br />

4- 5<br />

b z=<br />

d =<br />

f =<br />

n-j-1<br />

I. 2<br />

2 (n -j- 2)<br />

3- 4<br />

3 (" -f 3)<br />

o.f V.<br />

5. 6<br />

n<br />

— u<br />

1<br />

I —<br />

n4- I a<br />

I. 2<br />

l-f— n— I<br />

— u<br />

2. 3<br />

I • 2 (u -|- 2) u<br />

14--^^^^—<br />

II. 14


210<br />

©fftte vi i benne gormel n = —|, bo er<br />

(i4-u) ^ =<br />

I<br />

. + i^<br />

encr<br />

(i4-u)^ = i4-<br />

14-<br />

i-f-<br />

u<br />

1 +<br />

.+i^<br />

. + ^<br />

3tnvenbe vi nu benne gormel for ot finbe y^a, eg on;<br />

toge bet n«rmc(te aLVobcnt;'Jnl nt vffre m=, eg ffftte a —m'<br />

= r, fnn cr<br />

Va = r;;^:^^ = m ^14--^<br />

r<br />

eg nitfnn, ^vig vi ffftte —7 = u, cr<br />

in- I<br />

ya = m(i -j-u)^<br />

inbffftte vi nu i ben fnmmen^ffngcnbe SBr»f SSffrbien<br />

nf u, og multiplicere meb m, bn er<br />

2m'<br />

V^a = m X I 4^<br />

i-l<br />

4 m-<br />

i-i<br />

4 111<br />

0. f V.


211<br />

jpvornf bo let, vcb ot multiplicere virfetigt meb m, og ber;<br />

nfffl ^vcr enfelt Seeb meb 2m, ben for Q,vnbrot;


212<br />

5ogcg foe X cn egentlig SSr^f ligefom ovenfor (§.48),<br />

bo tnbfeeg, ^vor ^urtigt biffe Staffer convergerc.<br />

gor ot ubvifle e cfler ©runbtnllet nf be nnturlige 80*<br />

gorit^mec, ville vi ubvifle er, ^vilfet let fon (!ee eftec Stfff;<br />

fen (§. 50).<br />

S^emlig, bo<br />

y = Z^o^(i4-x), og oltfnn omvenbt e^ = i-j-x,<br />

fno er<br />

er = i4-y4. II 4-^1^4-<br />

I. 2 I. 2. 3<br />

ffftte vi nu y = —y, bn cr<br />

e-y = i-y4-^^ 1<br />

•' ' I. 2 1.2. 3 '<br />

J?erof finbe vi bo<br />

2y' , 2y*<br />

ey-e-y = 2y4-—;^4-<br />

1.2.3 • 1.2.3.4.5<br />

Sigdcbeg<br />

•^ \ ' 1.2.3 ' 1.2.3.4.5 ' J<br />

ey4-e-y = 24-^-j ^-^1<br />

1.2 1.2.3.4<br />

\ 1.2 1.2.3.4 J<br />

23cgge Stffffcr lobe fig fommcnligne meb F (p, q, r, x);<br />

fntte vi nemlig x = j ^ , ^vor k og k' 6cti;bebe to uenbc;<br />

ligt (tore Zal, fnn, noor vi fatte p = k, q = k', inb;<br />

fee vi, nt foovd pqx = y=, fom (p-j-i) (q4-i)x^<br />

= y% ba ©en^eben iffe vil gjere goctorcrne p og q, fom<br />

olt cre uenbdige, ftarre, og felgdigcn funne vi ffftte


eg<br />

Jtltfoo<br />

eT — e — T —<br />

C -j- e - T =<br />

eT — e — T<br />

=:2yF(k,k', 5,11)<br />

= 2F(k,k',5,ll)<br />

K'''''^'kk^)<br />

— Y . V<br />

F ^k, k', i, —J<br />

213<br />

SRen vi funne nu gjcme ^er i 5«fleren t«nfe eg k'<br />

foreget meb i, eflcr fot ligcftor meb k' -j- i, ubcn ot bette<br />

vilbe foronbre SSffrbien of Stffffcn, og foolebeg fammenligne<br />

ben meb gunctionen, fom ovenfor er ubviflct fom fommen;<br />

^ffngenbe Sdxsi (§. 62). SSi fjove bo<br />

ax = ^c^-^0, y' __ _2l<br />

i. I *4kk' I. 3<br />

_ (k'-j-i)(^-k) 4kk' _ y-<br />

• "" 1.4 * y* ~~ 3.5<br />

_ (k-j-i)(i-k') X-__ _r_<br />

cx ^ i 4kk' 5. 7<br />

3(ltfao<br />

0. f V.<br />

eT —e-T y_<br />

eT-J-e-T y^<br />

• + "^11


214<br />

Snbffftte-vi i benne gormd y =r i, foo cr<br />

e-j-C" —I<br />

I<br />

"^ e^4-i<br />

I<br />

I.I<br />

4.^-3<br />

+ 1,1<br />

1-4-3-^<br />

'+ i.i<br />

x4--^-^ 1.1<br />

x-f^-^<br />

SOiultipliccce vi ^eri Sebbene meb 3, 5, 7- i ^fffler<br />

eg Slffvncc, vifle SBreferne bortfolbe, eg vi cr^olbe, veb<br />

«t multiplicere i ZciHex og SRffvner meb e-'<br />

c' —I I<br />

e^4-l<br />

Sigclebeg, vcb<br />

1+' 3+<br />

ot ffftte y r=<br />

I<br />

r 1 I<br />

5 1 r<br />

e-j-i<br />

I<br />

6+--.<br />

lO-j—- —<br />

14-j-....<br />

S5ctegne vi benne fnmmcn^ffngenbe fdxet meb M, fno er<br />

e — I<br />

- = M<br />

e4-l<br />

1<br />

- i 1<br />

'<br />

er^olbe vi


3lltfao<br />

i-j-M<br />

*" 7—M<br />

215<br />

5:age vi f)craf ene, for ot ^ave et ilrcmpd poo ben<br />

uumcrifTe Stegniug, be 4 fremfotte Sceb, foo ^ove vi, veb ot<br />

860<br />

forvonblc ^jffbcbrefen poo fffbvonlig IBJoabe, M = —T-/-<br />

2721<br />

og for e = = 2,7182817 , fom ferft i bet<br />

1001<br />

(ibfle Secimol cr i for lifle (§. 50).<br />

§. 65. gor i fommen^ffngenbe S5ref ot ubvifle be<br />

Stffffcr, vi ^ave funbet for Sirfel; gunctioner, vifle vi ferfl<br />

tage Ubtri;ffene for sin z og cos z (§. 53). SSi ^ove bo<br />

sinz<br />

1.2.3 1.2.3.4.5<br />

z^ z"<br />

cos z =^ I j-<br />

1.2 1.2.3.4 1.2.3.4.5.6<br />

Siffe Stffffcr ere nitfnn neic be fomme, fom vi fonbt oven;<br />

for for eT — e-T og ey-{-e — r; tun finbeg ^er nfve;;lenbe<br />

5egn og gnctoren 2 bortfolber, oltfoo funne vi ffftte<br />

sinz = zF r k, k', f, —^ )<br />

cosz<br />

= F(k,k',i,_-Q<br />

g«lgdigen er^olbe vi, ligefom for^cn, Q,votienten of biffe<br />

Stffffcr, cfler


2l6<br />

cosz z'<br />

1-3<br />

I —<br />

z-<br />

3-5<br />

I -^<br />

5.7<br />

I<br />

z^<br />

7-9<br />

€t Ubtri;f, ^vig Sov vi longt ti;beligcce inbfee, enb ben,<br />

ber ^erj?er i feen (§. 53) fremfatte 3t«ffe for 2ongenten.<br />

2oge vi Ubtri;ffct for SBuen, bcftcmt vcb ^ongcnten,<br />

ibet vi ffftte tgz = t, foo er<br />

z = t —4-134->t=—f 1^4<br />

I 4- X<br />

fom ogfoo er ot fommcnligne meb loff -—^—, fung at<br />

I — X<br />

^er og pnbeg ofvejclenbe ?egn, og fom vi oltfoo funne ffftte<br />

ligeftort meb tF (;, i, ^, — t'),<br />

Sfltf'oo ec<br />

I<br />

I.I<br />

— t*<br />

1-3<br />

2.2<br />

t^<br />

.3-5 3^..<br />

r + " 4^4


£atfe vi ficv t z= 1, fnn er r. •=. 45°, nitfno<br />

I<br />

1 +<br />

I. I<br />

'1- 2<br />

, 3-5<br />

i-l-<br />

3-3<br />

5-7<br />

217<br />


Sni)|)olt) af begge S)e(e»<br />

%0t\te DeeL<br />

Snblebning . . . . ©ibex.<br />

SKatl^cmtttiEcng Scfinition 03 Snbbcling . . , §. 1-3..<br />

SRot^ematifle ©atninger • . . . . . . » § . 4.5.<br />

Scgn og 0runbf(«tningci: • S. 6.7.<br />

Slrit^metif . . ©ibe5.<br />

Zal forflaret; Snbbeling of Sirit^metifen . . §. 1,2.<br />

Set bccobifle lolfpftem 5. 3.<br />

(gengartebe ffolflerrclfer bcfincrebe . . . . . § . 4.<br />

Slbbition i bde 5Ettt . . . . . . . . . §. 5-10.<br />

©ubtroction t Ode a;al . . . . . . . . §. 11-15.<br />

©ommenfatte ©terrelfcr beftncrebe . . . . . § . 16.<br />

SJlultiplication i l;ele Zal §. 17-24.<br />

Sivifio*^' »)cle Stat . . . . . . . . . 5. 25-30.<br />

0icgning meb ben«vnte Stal . . . . . . . § . 31.<br />

©ecimol = asrefer . . . . . . . . . . § . 32.<br />

aibbition 09 ©ubtroction of Sccimal; SSr^let . §. 33.<br />

sDlultipltcatiott nf SecimoliSBrefer . . . . . § . 34.<br />

Sioifton of Sectmol:58r9ter . . . . . . . 5. 35.


219<br />

33laal, sprimtal, ftBllebg 5!Kaal ic 5. 36-40.<br />

Jatllebg betdigt Zal (communis diviilmis) . . 5. 41.42.<br />

SSreE beftneret, forfortet ic §. 43-47.<br />

Sibbition of SBretcr §.48.<br />

©nbtraction af SBreter . . . . . . . . § , 49.<br />

SKultiplication af SSteter §• 50.51.<br />

Sirifion of SBrefcr §. 52, 53.<br />

Sccimal=S8v»E til f«b»anlig SBvef 5. 54.<br />

Sjflibcbrot 5. 55.56.<br />

Sogflaorcgning 5. 57-60.<br />

Slbbition af aSogflaoflerrdfer . . , . . . § . 6i.<br />

Subtraction of SBogflovflerrelfcr §. 62.<br />

Slultiplication of SSogilavflerrelfcr . . . . § . 63. 64.<br />

Sivifion of SBogftaofterrclfcr . . . . . . § . 65.<br />

Hvaitat-- og enbiE=5Eal . . . . . . . . § . 66-71.<br />

aottbratet af ct asinomium . . . . . . . 5, 72.<br />

iQrabratrobg: fitractionen • §• 73. 74.<br />

enbng of ct SBinomium . . . . . . . , § . 75.<br />

eubiErobg = (ErtractioncH . . . . . . . . § . 76. 77.<br />

Sor^olb og spropottioner §. 78-82.<br />

Slrit^metiffe sptoportioncr §. 83.84.<br />

®eometrif!e sproportionct §. 85-87.<br />

gocanbringer meb geomcttiffe sproportioner . . §. 88-93.<br />

©ammenfatte gortjolb . . . . . . . . 5. 94.<br />

SlMVcnbclfc of sproportioner poo Olcgnla Sctri . §. 95.<br />

Omvenbt 3tegula Sctri . . . . . . . . § . 96.<br />

©amittcnfat SJicgula Sctri (Dlccftff Siegcl) . . 5. 97.<br />

Sjffiberegleit 5, 98.<br />

©clflabg: 09 a3lanbingg: meaning . . . . . § . 99.


220<br />

Signingct . . . . ^ . " » • . . . . §. 100-104.<br />

gigninger meb en UbcEjenbt of f#rfte ©rob . §, 105-110,<br />

Signinger meb ficve UbeEjenbte of ferfte ®rab 5. 111-113.<br />

SRaor er en Signing ubcflemt 5. 114.<br />

avabratif!e Signingct . . . . . . . . § . 115-121,<br />

Sogaritlinier . . . . . . , . . . . § . 122-128.<br />

StentcgiOiegning meb Sogaritl;mct . . . . §.129.<br />

gorfljct imellem clementwr 03 Oeicre Sltitl;mcttE 5. 130.<br />

©cometrie . . . . . . . . . ©ibe 85.<br />

Stumfterrelfcrne bcfinercbe 5. i-io.<br />

SSinfler, lobrette Sinier 5. ii-i8»<br />

^nraflellcr . . . . . . § . 19.20.<br />

giguver . . . . . • » §. 21-23.<br />

girEcl . . §. 24.<br />

Snbbeling i clementoir 03 Ijeicrc ©cometric,<br />

?planimetric 03 ©tcreometrie . . . . §. 25.<br />

©Ejarenbe 09 bererenbe SirElcr §. 26-28.<br />

6ongruentg:®rnnbf«tnin3Cn . . . . . . 5. 29.<br />

Slfle rette SSinElcr ere li3e(lote . . . . . § . 30.<br />

6on3ruentc Srianslcr §. 31-35.<br />

gorfIieHi3C gccntctriffe Dpsflver . . . . . § . 36-42.<br />

sRobocoinEler 09 S£opvintlcr §. 43-46*<br />

Wbvenbige SSinElcr. Snbbeling nf Svtanglcrne<br />

meb .^enfpn til SSiuElerne . . . . . 5. 47.48.<br />

©terfl ©ibe li33er ooerfot (lerfl SSinfel . . §. 49-5t><br />

©ibfte 5£ilf(Blbe of lEtiangletg (Songrucntg, Ztii<br />

ongler, 0»cri 2 ©iber fun ere ligeflorc . 5. 52-54.<br />

faroflcflc Sinier . §. 55-60.<br />

qiBe SJinElcr i et Itriangcl 2R 5. 61.


221<br />

qjaralldcgrammct ; ; . . 5. 62-67.<br />

5patallelcgrammer paa eeng ©vunblinie og $9ibc §. 68-72.<br />

Sen pptljagorifTe ©tstning §.73. 74.<br />

Sinier eg SSinfler oeb girflen §, 75-91.<br />

Snbflreonc og omflreone gignrer . . . . § , 92-94.<br />

IRegulcerc spolpgoner . . . . . . . . § . 95-97.<br />

giitEant og ©ctEant , §. 98,99.<br />

^proportion imeflem Sinier i Sriangler . . §. 100-104.<br />

£igebannebe ^dangler §. 105-112.<br />

g)roportionale Sinier i SirElcn . . . . . § . 113-115.<br />

@eomctrif!t at f«ge fjcrbe Jproportionals 09<br />

og aJJdlcmproportional: ©tervclfe . . §. 116-118.<br />

§)berfle 09 mellcmfle govljolb, S;iEant . . . §. 119-121.<br />

Edanglcrg 03 sparaHdogrammevg gorljolb . . §. 122-125.<br />

Oiabing, gemEant: og a;iEant:£ibcn banne ct<br />

retoinElct ^riaiigct §. 126.<br />

gorljolbafspolpgoncrgspevimetreogglabcinbl^olb §. 127-130.<br />

gigurcrg goroanbling-09 fipabratnr . . . §,131-138.<br />

Siettc Sinicrg Itbmaaling • §. 139.140.<br />

SSinElcrg 09 givEelbucrg Ubinaaling . . . . § . 141.142.<br />

glabcrg Ubttiaating . . . . . . . . . § . 143-147.<br />

eivElcng Ubmaaling . . . . . . . . . § . 148-153.<br />

Cp8«»er, oplefle veb Sllgcbra . . . . . 5. 154.<br />

3(nbcn ^aU<br />

ainbcn gifbeling. ©tereometrie . . . ©ibex.<br />

Sinicrg og ?planerg 3ndination S. 1-27.<br />

sptigmer 03 qjoraflelcpibcr . . . . . . § . 28-40.<br />

5Poramibcr . . . . . . . . . . . § . 41-45.<br />

Sylinbre S. 46.


222<br />

.Scglct §• 47'<br />

.Suglen §.48.49.<br />

Stcgularc Segemer §.50.<br />

£e3cmerg Itbmaalins . . . . , . . . . § • 5i-54'<br />

Sescmerg Doeifabe . . . . . . . . . § . 55*<br />

Susleng Ubmaaling . . . . . . . . . § . 56. 57-<br />

©tcreometrifle Dpgovcr, bel;anblebc vcb llgebro §. 58-61.1<br />

£rebie Slfbeling, Srigonometrie . . ©ibe<br />

Strigonomctnflc gunctioner . . . . . . . S. i-4'<br />

gormler for gunctioner of ©um 09 Sifferentg of<br />

SSinfler §. 5-9.<br />

5plan 09 fp^arif! Urigonomctde §. 10.<br />

CfictvinElcbc plane ariansler . . . , . . . . § • ii»<br />

©EjaovinElcbe plane ^iriongler . . . . . . § • 12-15.<br />

©pl;«nfl tngonomctdffe .^ovebformlet . . . 5. 16.17.<br />

SictvinElcbe fpt)«riflc 2;riangler . . . . . . § . 18.19-<br />

©EjavvinElcbe fp^ceriflc Srianglcr §. 20-22.<br />

©aupeg gormler 5. 23.<br />

31 r i 11) m e t i t<br />

spotcng, OJobfterrclfcv, imaginaive ©terrelfcr . §. x-io.<br />

3iene Ijeiere 9ffgoarioncr §. xi-15.<br />

evponCntiaU^ffqoaticner . . . . . . . . § . 16.17.<br />

Ubeftemte Dpgaver §. 18-23.<br />

y?eicre ?ffq»ationer . . ' . . . . . . , § . 24-29.<br />

Dpte^ning af bt cubific ?eq»ationer . . . . 5. 30. 31.<br />

3lritOmctif!e sprogregfipncr §. 32-35.<br />

.S>eierc aritl)metifFe attcffer, figurlige Zal . . §, 36-39.<br />

©comctrifFe $progrcgfioner . §. 40-42.


223<br />

Ubeftemte eocfficicnter^ SDlctbobe §• 43- 44.<br />

iBincmial: gurmlen §,45.46.<br />

spolpnomiaUgormlcn 5. 47.<br />

SiuEEcr for Sogaritbmer §. 48-51.<br />

JRceEEcr for tvigonometvifle gnnctioner og TT . §• 52-56.<br />

Snterpolationg: gormler §. 57-59-<br />

Sjatbebref §. 60-65.


9v e t t e I f e r.<br />

Site 5. Silt. 20. "ba" Icei "a(tfaa"<br />

— 10. — 21. EF Uxi ET<br />

— 10. — 23. "bnigcS" iKi "bt'mgcS"<br />

— 12. — 29. LO tocS LR<br />

— 16. — 19. LKD:VRP tceSVRPtLKD<br />

— 17. — 9. "-^^riSmct" t(Ko "ipi^ramibct"<br />

— 18. — II. GC tees EC<br />

— 25. — 18- "

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