Contour integral (from complex analysis)

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Homework Statement



let g denote the elliptic arc parametrized by z(t) = 2cost + 3isint, for t between 0 and pi/2 (inclusive).

Evaluate the integral of f(z) = z[sin(pi*z^2) - cos(pi*z^2)] over g.



Homework Equations



If g is determined by the function z mapping from [a,b] to C and f maps from g to C, then the integral of f over g is defined as the integral (from a to b) of f of z(t) times z'(t).

(sorry for writing the equations out in words, I don't have any formatting software)



The Attempt at a Solution



I started by finding z'(t) = -2sint + 3icost and attempting to find f(z(t)), but I got a really complicated function and at that point I figured I must be going about it the wrong way.

I tried to find an identity that would allow me to simplifiy f(z) but I couldn't find anything.

At this point I really have no idea how to proceed.
 
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If f(z) is analytic, what do you know about its integral along a contour between two points?
 
hmm...I don't know. It doesn't say so in the problem. Is that something I should be able to recognize?
 
Yes, or at least, it's something they want you to learn. I imagine that's the point of this problem.
 
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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