# Math Help - Double integration

1. ## Double integration

Need help to show that double integrate [1 0] [1 0] 1/(1-xy) dx dy gives pi^2 / 6 by applying the substitution:

x = (sqrt2 sin theta - v) / sqrt2
y = (sqrt2 sin theta + v) / sqrt2

2. ## Re: Double integration

Hey TaTzRE66.

Can you show us what you tried? What is the Jacobian, new limits and new integral used for the substitution?