# Changing to polar integration

1. Nov 4, 2013

### PsychonautQQ

1. The problem statement, all variables and given/known data
Evaluate the integral by changing to polar coordinates.

Double Integral: (x^2+y^2)dydx, where dy is bound between 0 and (4-x^2)^(1/2) and dx is between and -2 and 2

3. The attempt at a solution
okay so I can turn this into
Double Integral: (r^2)rdrdθ

My question is on the parameters of dr and dθ
I really want to say dr goes from 0 to 2.
does dθ go from 0 to 2∏

2. Nov 4, 2013

### Simon Bridge

If that is what you really want to say, then what is stopping you?

note:
it is not dr that goes from 0 to 2, it is r that does that. etc.

3. Nov 4, 2013

### Staff: Mentor

Can you describe, in words, the region over integration takes place? If you understand this region, you'll pretty much have answered your question about θ.

4. Nov 4, 2013

### LCKurtz

I second Mark's comment. Tell us what the region looks like. For all we know, your original integral may be set up wrong.