Parseval Relation/Fourier Series

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Homework Statement



Slope-matched parabolic sections. Consider the function of period 4 defined over the interval [-2,2] by the equations:

f(t) = 2*t-t^2 for 0<t<2 and f(t) = 2*t+t^2 for -2<t<0

It has a Fourier expansion \sum_{m=0}^\infty \frac{32}{\pi^3*(2m+1)^3} sin((2m+1) \frac{\pi}{2} t)

Use Parseval's relation to compute the sum \sum_{m=0}^\infty \frac{1}{(2m+1)^6}

Use the extended Parseval's relation and Fourier series calculated in this handout to compute the sums \sum_{m=0}^\infty \frac{1}{(2m+1)^4} and \sum_{m=0}^\infty \frac{(-1)^m}{(2m+1)^5}

Answers: \frac{\pi^6}{960} ; \frac{\pi^4}{96} ; \frac{5 \pi^5}{1536}

Homework Equations



Parseval's Relation/Parseval's Extended Relation



The Attempt at a Solution



Okay, we got the first part, the pi to the six over 960. What we don't get is how to use the extended Parseval relation to find the second parts. We tried writing up a Fourier series for an antisymmetric square wave, but we weren't getting anywhere with that. Basically, we're clueless on the second two.

Any ideas?
 
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Writing out how you solved the first part as well as the P.E.R. might help to elicit responses.
 
We got it...turned out we were just confused by the phrasing, and the problem was actually really easy. Go figure. Thanks!
 
Always glad to help :)
 
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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