Òîä³ ð³âíÿííÿ (10.7.3) ìîæíà çàïèñàòè ó âèãëÿä³: ∂u ∂ϕ +λ = 0 . ∂x ∂x Îñòàòî÷íî ñòàö³îíàðí³ òî÷êè óìîâíîãî åêñòðåìóìó âèçíà- ÷àþòüñÿ ç ñèñòåìè òðüîõ ð³âíÿíü ⎧ ∂f ∂ϕ ⎪ +λ = 0, ∂ x ∂ x ⎪ ⎪ ∂ f ∂ϕ ⎨ +λ = 0, ⎪ ∂ y ∂ y ⎪ϕ ( xy , ) = 0. ⎪ ⎩ ßêùî ðîçãëÿíóòè ôóíêö³þ ( x, y, ) f( x, y) ( x, y) (10.7.4) λ = +λϕ , òî çíàõîäæåííÿ óìîâíîãî åêñòðåìóìó ôóíêö³¿ f(x, y) çâåäåòüñÿ äî çíàõîäæåííÿ áåçóìîâíîãî åêñòðåìóìó ôóíêö³¿ (x, y, λ), îñê³ëüêè ñèñòåìà (10.7.4) ð³âíîñèëüíà ñèñòåì³ ⎧∂ ⎪ = 0, ⎪ ∂ x ⎪ ∂ ⎨ = 0, ⎪ ∂ y ⎪∂ ⎪ = 0. ⎩ ∂λ Ôóíêö³ÿ íàçèâàºòüñÿ ôóíêö³ºþ Ëàãðàíæà. Õàðàêòåð óìîâíîãî åêñòðåìóìó, òàê ñàìî, ÿê ³ áåçóìîâíîãî, âèçíà÷à- ºòüñÿ çà òåîðåìîþ 10.6.2. ßêùî ñòàâèòüñÿ çàäà÷à íà åêñòðåìóì ôóíêö³¿ u = f(x 1 , x 2 ,…, x n ) ³ç çâ’ÿçêàìè ϕ j (x 1 , x 2 ,…, x n ) = 0, j=1,m , m < n, (10.7.5) òî ñêëàäàºòüñÿ ôóíêö³ÿ Ëàãðàíæà m =f(x,x, K,x)+ ∑ λϕ(x,x, K ,x). (10.7.6) 1 2 n j j 1 2 n j= 1 ∂ Íåîáõ³äí³ óìîâè = 0( i = 1, n) ∂x , ðàçîì ç ð³âíÿííÿìè i (10.7.5), óòâîðþþòü ñèñòåìó ð³âíÿíü, ç ÿêî¿ âèçíà÷àþòüñÿ êîîðäèíàòè ñòàö³îíàðíèõ òî÷îê. Ôóíêö³ÿ (10.7.6) çâîäèòü çàäà÷ó óìîâíîãî åêñòðåìóìó äî áåçóìîâíîãî. Ïðèêëàä 10.7.1. ϳäïðèºìñòâî âèð³øèëî ùîì³ñÿöÿ âèä³ëÿòè 140 000 ãðí íà âèðîáíèöòâî íîâî¿ ïðîäóêö³¿. Ñåðåäíÿ çàðîá³òíà ïëàòà íà ï³äïðèºìñòâ³ äîð³âíþº 400 ãðí., à âàðò³ñòü îäèíèö³ ñèðîâèíè – 100 ãðí. Ïîòð³áíî âèçíà÷èòè, ÿêó ê³ëüê³ñòü ðîáî÷èõ k ³ ÿêó ê³ëüê³ñòü ñèðîâèíè c íåîáõ³äíî ïðèäáàòè ï³äïðèºìñòâó äëÿ îäåðæàííÿ íàéá³ëüøîãî îáñÿãó ïðîäóêö³¿ Q, ÿêùî â³äîìî, ùî Q =80k +20c – k 2 – c 2 + kc. (10.7.7) Çã³äíî ç óìîâîþ âåëè÷èíè ñ ³ k ïîâ’ÿçàí³ ì³æ cîáîþ òàê: 400k + 100c = 140 000. (10.7.8) Ð î ç â ’ ÿ ç à í í ÿ. Öå çàäà÷à íà óìîâíèé åêñòðåìóì 2 2 ( , ) 80 20 , 400 100 140000 Qkc 14444444444444424444444444444 = k+ c −k − c + kc k + c = 43 2 2 ( , , ) 80 20 (400 100 14000) Lkcλ = k+ c−k − c + kc+λ k+ c− ⎧∂L ⎪ = 80 − 2k+ c + 400 λ = 0 ∂ k ⎪ ⎧ c − 2k + 400λ = −80 ⎪∂ L ⎪ ⎨ = 20 − 2c + k + 100 λ = 0 ⇒ ⎨k − 2c+ 100 λ = −20 ⎪∂c ⎪ 400k + 100 c = 14000. ⎪∂L ⎩ ⎪ = 400k + 100c − 140000 = 0 ⎩ ∂λ Ðîçâ’ÿçóþ÷è îñòàííþ ñèñòåìó áóäü-ÿêèì ñïîñîáîì, îòðèìàºìî (ïåðåâ³ðòå!): k = 30, c = 20, λ =–10 –1 . 390 391
Òàêèì ÷èíîì, ìè âèçíà÷èëè ºäèíó òî÷êó Ì 0 (30, 20), ÿêà ï³äîçð³ëà íà åêñòðåìóì ôóíêö³¿ Q(k, c). Çàñòîñóâàííÿ òåîðåìè 10.6.1 äî ôóíêö³¿, ñòðóêòóðà ÿêî¿ âèçíà÷àºòüñÿ ôîðìóëîþ (10.7.7) ³ç çâ’ÿçêîþ (10.7.8), âèÿâëÿº, ùî â òî÷ö³ Ì 0 (30,20) ôóíêö³ÿ Q(k, c) ìຠìàêñèìóì (ïåðåâ³ðòå!): ( ) Qmax = Q 30,20 = 2100 îäèíèöü ïðîäóêö³¿. Îòæå, íà ïîñòàâëåíå çàïèòàííÿ â³äïîâ³äü îäíîçíà÷íà: äëÿ ìàêñèìàëüíîãî âèðîáíèöòâà ïðîäóêö³¿ òðåáà çàáåçïå÷èòè 30 ðîáî÷èõ ì³ñöü ³ ïðèäáàòè 20 îäèíèöü ñèðîâèíè. Çàóâàæåííÿ. Ïîñòàâëåíó çàäà÷ó ìîæíà ðîçâ’ÿçàòè ³ ³íøèì ñïîñîáîì, à ñàìå: øëÿõîì çâåäåííÿ çàäà÷³ íà óìîâíèé åêñòðåìóì äî çàäà÷³ íà çâè÷àéíèé åêñòðåìóì. Äëÿ öüîãî òðåáà ³ç ð³âíîñò³ (10.7.8) îäíó âåëè÷èíó, íàïðèêëàä ñ âèðàçèòè ÷åðåç k ³ ï³äñòàâèòè â ôîðìóëó (10.7.7), à ïîò³ì äîñë³äèòè íà åêñòðåìóì. ÂÏÐÀÂÈ Çíàéòè óìîâíèé åêñòðåìóì ôóíêö³¿: x y 10.26. z = x 2 + y 2 ïðè + = 1. 2 3 2 2 2 x y z 10.27. u = x + y + z ïðè + + = 1 2 2 2 , äå a > 0, b > 0, c >0. a b c 10.28. u = xy 2 z 2 ïðè x + y + z = 12, äå x > 0, y > 0, z >0. ³äïîâ³ä³: â 10.26 min ó òî÷ö³ â 10.27 min ó òî÷ö³ 2 2 2 ⎛ a b c ⎞ ⎜− , − , − ⎟ ⎝ λ λ λ ⎠ λ >0, 2 2 2 λ= a + b + c ; â 10.28 min ó òî÷ö³ ⎛18 12 36 ⎞ ⎜ , , ⎟ ⎝13 13 13 ⎠ ; ïðè λ
- Page 1 and 2:
̲ͲÑÒÅÐÑÒÂÎ ÎѲÒ
- Page 3 and 4:
2.4. Ðàíã ìàòðèö³ ......
- Page 5 and 6:
7.9. Ïîõ³äí³ âèùèõ ïî
- Page 7 and 8:
10.2. Ãðàíèöÿ ³ íåïåð
- Page 9 and 10:
Ïåðåäìîâà Ç óñ³õ ñî
- Page 11 and 12:
äåòüñÿ” âèêîðèñòî
- Page 13 and 14:
1 îòðèìàºìî äð³á m = 2
- Page 15 and 16:
1.2.7. Ìîäóëü ä³éñíîã
- Page 17 and 18:
Òåìà 2 Îñíîâè àëãåá
- Page 19 and 20:
Öÿ ñèñòåìà ð³âíÿíü
- Page 21 and 22:
2 0 . Ó ÿêîñò³ åëåìåí
- Page 23 and 24:
Äîâ³ëüíèé åëåìåíò
- Page 25 and 26:
Ïðèêëàä 2.2.2. Çíàéòè
- Page 27 and 28:
a a ... a a ... a a a ... a a ... a
- Page 29 and 30:
Òîä³ a 12 12 ∆ 1 =∆+ m =∆
- Page 31 and 32:
Äâ³ ìàòðèö³ À ³ Â íà
- Page 33 and 34:
3 0 . Îá÷èñëèòè àëãåá
- Page 35 and 36:
ÒÅÌÀ 3 ÑÈÑÒÅÌÈ Ë²Í²
- Page 37 and 38:
Ïðè ðîçâ’ÿçàíí³ ñè
- Page 39 and 40:
äå æa11 a12 ... a ö 1n a21 a22
- Page 41 and 42:
Ðîçâ’ÿçàííÿ. Øëÿõî
- Page 43 and 44:
3.3. Êîðèñòóþ÷èñü ïð
- Page 45 and 46:
Äëÿ äàíî¿ òî÷êè Ì â
- Page 47 and 48:
Îòæå, êîîðäèíàòè òî
- Page 49 and 50:
ìèì îáìåæåííÿì, îáó
- Page 51 and 52:
Ïðèêëàä 4.2.6. Ñêëàñò
- Page 53 and 54:
Ïðèêëàä 4.2.14. Çíàéòè
- Page 55 and 56:
ð³âíÿííÿìè ïåðøîãî
- Page 57 and 58:
ßêùî k çàäàíå ÷èñëî,
- Page 59 and 60:
3) ∆ =0 ³ ∆ x = 0, ∆ y = 0.
- Page 61 and 62:
ÿêèé íàðîäèâñÿ â ëþ
- Page 63 and 64:
º àíàë³òè÷íå ð³âíÿ
- Page 65 and 66:
4.5. ÏÎÍßÒÒß ÏÐΠвÂÍ
- Page 67 and 68:
Ç ðîçãëÿíóòîãî ïðè
- Page 69 and 70:
⎧1 ⎫ Ïðèêëàä 5.1.10. Ï
- Page 71 and 72:
5.1.5. Îñíîâí³ òåîðåì
- Page 73 and 74:
Îòðèìàëè, ùî ð³çíèö
- Page 75 and 76:
 òàê³é çàãàëüí³é ï
- Page 77 and 78:
n n 1 ⎛⎛1+ 5⎞ ⎛1− 5⎞
- Page 79 and 80:
1. Àíàë³òè÷íèé ñïîñ
- Page 81 and 82:
òâ³, ïðè òåõí³÷íèõ
- Page 83 and 84:
4. Äëÿ ïîáóäîâè ãðàô
- Page 85 and 86:
Ðîçâ’ÿçàííÿ. Íåõàé
- Page 87 and 88:
Öÿ ôóíêö³ÿ ÿâëÿº ñî
- Page 89 and 90:
Çã³äíî ç îçíà÷åííÿ
- Page 91 and 92:
sin x- 0 < x- 0
- Page 93 and 94:
Îçíà÷åííÿ 6.3.5 Ôóíêö
- Page 95 and 96:
6.3.6. Ãëîáàëüí³ âëàñ
- Page 97 and 98:
Ñïðàâåäëèâ³ñòü ôîð
- Page 99 and 100:
6.23. Îá÷èñëèòè ãðàíè
- Page 101 and 102:
Çà ïåð³îä ÷àñó â³ä t
- Page 103 and 104:
Ïðèêëàä 7.3.2. Ïîêàçà
- Page 105 and 106:
 ÿêîñò³ ïðèêëàäà ð
- Page 107 and 108:
Òåîðåìà 7.6.2 (ïðî äèô
- Page 109 and 110:
Òàáëèöÿ ïîõ³äíèõ ñ
- Page 111 and 112:
7.13. r(ϕ) =ϕ sin ϕ + cos ϕ; î
- Page 113 and 114:
7.9.8. Çíàõîäèìî y′: Ò
- Page 115 and 116:
Ôóíêö³ÿ ïðîïîçèö³¿
- Page 117 and 118:
Îñê³ëüêè â êðèòè÷í
- Page 119 and 120:
ïðè ∆x =1 i x=1000: (∆y)⏐x
- Page 121 and 122:
Íàñë³äîê 3. ßêùî íà
- Page 123 and 124:
7.14.9. = ln x 1/ x = 1/ x 1 − =
- Page 125 and 126:
Çàóâàæåííÿ. Ðîçêëà
- Page 127 and 128:
Îö³íèìî n ( ) n+ 1 θx n+ 1
- Page 129 and 130:
Çâ³äñè ó êð - ó äîò
- Page 131 and 132:
Ð î ç â ’ ÿ ç à í í ÿ.
- Page 133 and 134:
âè áóäåòå âèâ÷àòè ó
- Page 135 and 136:
8.3. ⎛ ∫ ⎜sin x+ ⎝ 3 ⎞ dx
- Page 137 and 138:
8.12. ∫ sin( ax + b) dx ; 8.13.
- Page 139 and 140:
Ïåðøèé òèï äîäàíê³
- Page 141 and 142:
8.5. ²ÍÒÅÃÐÓÂÀÍÍß ÄÅ
- Page 143 and 144:
6 4 1 1 1 5 1 3 = ∫t − dt+ ∫t
- Page 145 and 146: [ñ, b] ñåãìåíòà [a, b] ¿
- Page 147 and 148: 9.2.1. Îçíà÷åííÿ òà óì
- Page 149 and 150: 4. ßêùî ôóíêö³ÿ ó = f(
- Page 151 and 152: 9.4. ÎÑÍÎÂÍÀ ÔÎÐÌÓËÀ
- Page 153 and 154: â³äíîñò³ äî ôîðìóë
- Page 155 and 156: Îçíà÷åííÿ 9.6.1. Íåâë
- Page 157 and 158: ³ îñê³ëüêè +∞ ∫ 1 ðî
- Page 159 and 160: Ïðèêëàä 9.6.12 (òåîðåò
- Page 161 and 162: Ïðèêëàä 9.7.2. Îá÷èñë
- Page 163 and 164: Îñê³ëüêè ôóíêö³ÿ ó
- Page 165 and 166: Ãðàíèöÿ ö³º¿ ñóìè ï
- Page 167 and 168: Ð î ç â ’ ÿ ç à í í ÿ.
- Page 169 and 170: Òîä³ ìîæíà ïîêàçàò
- Page 171 and 172: 4 3 ∆Ψ = 10 − 10 = 9000 . Îò
- Page 173 and 174: ïàäຠç íàö³îíàëüí
- Page 175 and 176: Çàóâàæåííÿ 2. Àíàëî
- Page 177 and 178: 10.2. ÃÐÀÍÈÖß ² ÍÅÏÅÐ
- Page 179 and 180: Öå ð³âíÿííÿ ïðÿìî¿,
- Page 181 and 182: Öåé æàðò³âëèâèé åê
- Page 183 and 184: äàòêîâ³é âàðòîñò³
- Page 185 and 186: Îçíà÷åííÿ 10.4.2 Äèôå
- Page 187 and 188: ∂u äå ( i = 1, 2, K , n) ∂x
- Page 189 and 190: Àíàëîã³÷íî ( 0, 0 ) ( 0,
- Page 191 and 192: Çàóâàæèìî, ùî ïîíÿò
- Page 193 and 194: Òîä³: 1) ÿêùî a a a a > 0,
- Page 195: ÂÏÐÀÂÈ Äîñë³äèòè í
- Page 199 and 200: Ðèñ. 10.21 ³äîìèé Îìó
- Page 201 and 202: ßñíî, ùî âàð³àíò ë³
- Page 203 and 204: 11.1.3. Ïðî â³ëüíå ïàä
- Page 205 and 206: ñòå, òî ìè çìîæåìî é
- Page 207 and 208: êîîðäèíàò (ðèñ. 11.4).
- Page 209 and 210: ÂÏÐÀÂÈ Ðîçâ’ÿçàòè
- Page 211 and 212: ÂÏÐÀÂÈ Ðîçâ’ÿçàòè
- Page 213 and 214: Äàë³ âàð³þºìî ñòàë
- Page 215 and 216: 11.6.2. ˳í³éí³ îäíîð³
- Page 217 and 218: Òîä³ ( ) ( ) y2 x ≡λy1 x ,
- Page 219 and 220: 2x Çàãàëüíèé ðîçâ’ÿ
- Page 221 and 222: y′ ÷.í. = e x (2Ax +Ax 2 ), y
- Page 223 and 224: x = + + + . 2 2 5 y x c1 c2x c3 x
- Page 225 and 226: Ô(t) =7⋅ 10 6 +3⋅ 10 6 e -0,1t
- Page 227 and 228: S n 1 1 1 = + + K + 1⋅2 2⋅ 3 n
- Page 229 and 230: Îñê³ëüêè ðÿä (12.2.7) ç
- Page 231 and 232: Çàóâàæåííÿ. Ðÿäè ç
- Page 233 and 234: íà çàâæäè íå ïîðîæí
- Page 235 and 236: ÂÏÐÀÂÈ Âèçíà÷èòè ³
- Page 237 and 238: 12.5.6. Äîâåäåííÿ ôîðì
- Page 239 and 240: êö³þ, êîòðó íàé÷àñò
- Page 241 and 242: Âèðàç âèäó a+bi=z, äå à
- Page 243 and 244: òî z z r (cos ϕ + isin ϕ ) r (c
- Page 245 and 246: 13.16. z =− 2+ 2 3i ; 13.17. z =
- Page 247 and 248:
14.2.4. Êîðåí³ òà ¿õí³
- Page 249 and 250:
y ⎛ π ⎞ x tg α= k , k ; ctg (
- Page 251 and 252:
1 2 tg α+ ctg α= = sin αcos α s
- Page 253 and 254:
14.4. ÅËÅÌÅÍÒÈ ÂÈÙί
- Page 255 and 256:
14.5. ÃÐÀÔ²ÊÈ ÄÅßÊÈÕ
- Page 257 and 258:
14.5.11. y = arctg x (ðèñ. 14.19
- Page 259 and 260:
14.7. ÍÀÁËÈÆÅÍÅ ÇÍÀ×Å
- Page 261:
Ê36 Êåðåêåøà Ï. Â. Ëå