1. ## Definite Integral

Evaluate:

$
\int_{0}^{1}\frac{2x-(1+x^2)^2 cot^{-1}x}{(1+x^2)(1-(1-x^2)cot^{-1}x)}dx
$

2. Originally Posted by pankaj
Evaluate:

$
\int_{0}^{1}\frac{2x-(1+x^2)^2 cot^{-1}x}{(1+x^2)(1-(1-x^2)cot^{-1}x)}dx
$
Did you try substituting $x = \cot \theta$ ?