Integrals using u substitution

[howsockgothap]

Homework Statement

Using substitution, find the integral of 32x²/(2x+1)³

Homework Equations

The Attempt at a Solution

I initially tried plugging u in for 32x² but that wouldn't work because it won't cancel out with the problem below it anyway. I'm pretty sure we are not expected to multiply the bottom function out, so how would I go about doing this?

 

[ƒ(x)]

use partial fractions

 

[Dick]

Just use u=2x+1. You would have to do it anyway after partial fractions. So x=(u-1)/2. Then just expand the numerator.