29.01.2013 Views

Problems in Mathematical Analysis.pdf - pwp.net.ipl.pt

Problems in Mathematical Analysis.pdf - pwp.net.ipl.pt

Problems in Mathematical Analysis.pdf - pwp.net.ipl.pt

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

86 Extrema and the Geometric Applications of a Derivative [Cfi. 3<br />

Example 5. F<strong>in</strong>d the greatest and least values of the function<br />

on the <strong>in</strong>terval P/2<br />

Solution. S<strong>in</strong>ce<br />

it follows that the critical po<strong>in</strong>ts of the function y are *, = 1 and<br />

Fig. 24<br />

Compar<strong>in</strong>g the values of the function at these po<strong>in</strong>ts and the values of the<br />

function at the end-po<strong>in</strong>ts of the given <strong>in</strong>terval<br />

we conclude (Fig. 25) that the function atta<strong>in</strong>s its least value, m=l, at<br />

the po<strong>in</strong>t x=l (at the m<strong>in</strong>imum po<strong>in</strong>t), and the greatest value A4 = ll<br />

at the po<strong>in</strong>t *=2 J<br />

/i (at the right-hand end-po<strong>in</strong>t of the <strong>in</strong>terval).<br />

Determ<strong>in</strong>e the <strong>in</strong>tervals of decrease and <strong>in</strong>crease of the func-<br />

1ions:<br />

811. y=l 4* jf. *>- i<br />

2<br />

812. = .<br />

{/ (* 2)<br />

813. y = (A:+4) s .<br />

814. = 817. =<br />

{/ *'(*- 3).<br />

818.<br />

Y<br />

= (x<br />

o

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!