Optimizing Integration: Converting to Polar Coordinates

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PsychonautQQ
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Homework Statement


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


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∏
 
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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.
 
PsychonautQQ said:

Homework Statement


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


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