Calculating Curve Integrals with the Del Operator: A Pain in the Brain?

Karl Karlsson
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Homework Statement
Consider the vector field
##\vec v = exp(\frac {xy} {r_0^2}) [\frac {z} {r_0^2} (x\vec e_1 + y\vec e_2) + \vec e_3] + \frac {1} {r_0} (x\vec e_2 - y\vec e_1) + cos(\frac {z} {r_0})\vec e_3##
where ##r_0## is a constant with dimension length.

a) Calculate ##\nabla\cdot\vec v## and ##\nabla\times\vec v##.
b)Calculate the circulation integral $$\oint_Γ \vec v \,d\vec S$$ where Γ is the curve that is parameterized by ## x = r_0cos(t), y = r_0sin(t), z = r_0cos^2(2t), (1 < t < 2\pi)##
Relevant Equations
##\vec v = exp(\frac {xy} {r_0^2}) [\frac {z} {r_0^2} (x\vec e_1 + y\vec e_2) + \vec e_3] + \frac {1} {r_0} (x\vec e_2 - y\vec e_1) + cos(\frac {z} {r_0})\vec e_3##
My attempt is below. Could somebody please check if everything is correct?
Skärmavbild 2020-09-04 kl. 18.59.53.png

Skärmavbild 2020-09-04 kl. 19.00.04.png

Skärmavbild 2020-09-04 kl. 19.00.13.png

Thanks in advance!
 

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This problem looks like it is setup to cause calculation pain in the brain ?:).

Using wolfram I checked your answers for the divergence and the curl and I found them to be correct.

Cant find an easy way to check the curve integral. That calculation is really a pain in the brain...
 
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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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