Question #7c0a6

1 Answer
Oct 30, 2017

#pi^2/8#

Explanation:

This integral can be approached by considering a suitable u substitution

Let #u=sin^-1x#
We can differentiate this implicitly;
#sinu = x#
#cosu*(du)/dx = 1#
#(du)/dx = 1/cosu#

Now considering how #sinu = x# and how # cos^2x+sin^2x=1#
So hence #cosu = root2 (1-x^2)#

Hence #du = (dx)/(root2 ( 1-x^2))#

Hence the intergal becomes #int u du#
#Hence; (1/2)u^2 + c#

Hence the antiderivative is #1/2 (sin^-1x)^2 +c #

Hence evaluating from 0 to 1 we get;

# 1/2 (pi/2)^2 = pi^2/8#