Limitations of the divergence theorem

blade123
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Homework Statement



Evaluate the surface integral F * dr, where F=<0, y, -z> and the S is y=x^2+y^2 where y is between 0 and 1.

Homework Equations



Divergence theorem

The Attempt at a Solution



I just got out of my calculus final, and that was a problem on it. I used the divergence theorem and got div F = 0 + 1 - 1 =0

Therefore the triple integral and therefore the surface integral will return 0. Is this true? I thought it was too easy, I can't see why it wouldn't be true.

Is there a limitation I glossed over?
 
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Don't think so, that should work. Try evaluating the surface integral and seeing if it also returns 0.
 
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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