# Double integral using polar coordinates

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I wanted to know why they integrated from 0 to pi and not from 0 to 2pi

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LCKurtz
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The question is in the paint document

I wanted to know why they integrated from 0 to pi and not from 0 to 2pi

Draw a picture of the region.

Draw a picture of the region.

There that is the region I believe

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Sorry I just looked at the question again.. it said above the x-axis

LCKurtz
Homework Helper
Gold Member

One last question. When is it best to use polar coordinates rather than spher. coord. For instance if I integrating a cylinder I would use polar and If I was integrating a cone or a ellipsoid I should use spher. coord. But what about elliptical parabaloids or eliptic hyperbolas of one or two sheets?

To answer my above question (post # 6) I am guessing is depends on my region on the xy plane that I am integrating over..

LCKurtz