Antiderivative of anti-trigs(arctan)

[vipertongn]

Homework Statement

arctan(x)/(1+x2). finding the antiderivative

Homework Equations

arctanx=1/1+x^2

The Attempt at a Solution

I tried pulling out arctan(x) S 1/(1+x^2) dx --> arctan^2(x)+c but the answer also has a 1/2 in front of the arctan...where'd that come from?

 

[Gib Z]

You can't just pull out the arctan! You can only pull out constants. Try making a u-substitution.