(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

∫1/x^2*√25-x^2

2. Relevant equations

√a^2-x^2 , x=a sin (theta) , -pi/2 less than or equal theta less than or equal pi/2 Identity 1-sin^2 theta= cos^2 theta

table of trigonometric substitutions

3. The attempt at a solution

x=5 sin theta

dx= 5 cos theta dtheta

theta=arcsin (x/5)

√25-x^2=5 cos theta

∫5 cos theta / 25 sin^2 theta * (5cos theta)=1/25 ∫sin^2 theta d theta

=1/25 - cos^2 theta+c

= -1/25 cos^2 (arcsin(x/5) +c

but the answer in the back of the book is -√25-(x^2)/(25x) +c

what did i do wrong

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# Help with trigonometric substitutions

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