# Trigonometric substution

1. Mar 2, 2012

### anna062003

Evalutate ∫ytan^-1(y) dy

i don't know how to start, can somebody tell me how?

2. Mar 2, 2012

### Dick

It's not a trig substitution problem, it's an integration by parts problem. Try u=arctan(y) and dv=ydy.