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

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The discussion revolves around the challenges of calculating curve integrals using the Del operator. A user seeks verification of their calculations, expressing frustration over the complexity of the problem. Another participant confirms the correctness of the divergence and curl calculations but notes difficulty in checking the curve integral. The conversation highlights the inherent difficulties in these mathematical operations. Overall, the thread underscores the complexity of curve integrals in vector calculus.
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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Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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