# Homework Help: Find the indefinite integral

1. Apr 19, 2015

### brandon hodoan

1. The problem statement, all variables and given/known data
Find the indefnite integral using trig substitution.
∫[(x^2) / (1+x^2)]dx

2. Relevant equations
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3. The attempt at a solution

2. Apr 20, 2015

### Delta²

The denominator should be $sec^2(\theta)$ so all you left with is $\int tan^2\theta d\theta$. To calculate that make the substitution $x=tan\theta$ and notice that $dx=(1+tan^2\theta)d\theta$.