Convert to cylindrical coordinates

caliguy
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Evaluate by changing to cylindrical coordinates

\int from 0 to 1 \int from 0 to (1-y^2)^1/2 \int from (x^2+y^2) to (x^2+y^2)^1/2 (xyz) dzdxdy

I came to an answer of integral from 0 to pi integral from 0 to 1 integral from r^2 to r (rcos\thetarsin\thetaz) r dzdrd\theta
Is this the correct answer?
 
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Hello Caliguy. Click on the expression below to see how to post it so it is readable in tex:

\int_0^1 \int_0^{\sqrt{1-y^2}}\int_{x^2+y^2}^{\sqrt{x^2+y^2}}xyz\ dzdxdy

This looks like a first octant integral. Check your \theta limits.
 
To me they seem right, doesn't theta go from zero to pi? after graphing it it looks like a half a circle... maybe I'm overlooking something?
 
Neither x nor y get negative in your original integrals.
 
So theta only goes from 0 to pi/2 right?
 
caliguy said:
So theta only goes from 0 to pi/2 right?

Yes.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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