(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

2. Relevant equations

Equations to compute fourier series given in question

3. The attempt at a solution

Ok so I've just done this problem and I'm having some trouble computing the fourier series of [itex]x^{2}[/itex] between -∏ < ∏

So first I calculate [itex]a_{0}[/itex] and that turns out to be [itex]\frac{∏^{2}}{3}[/itex], which according to wolfram is right.

Next [itex]a_{n}[/itex], which is the one I'm having trouble with. Essentially you have to do integration by parts twice (right?) and I end up getting something quite messy, as does wolfram

http://www.wolframalpha.com/input/?i=integrate+x^2+cos+%28n+x%29+dx+from+x%3D-pi+to+pi

Is there any way to clean this up for when I plug [itex]a_{n}[/itex] into the final formula?

[itex]b_{n}[/itex] is 0 obviously so there's no issue there (since it's an even function times an odd function).

Thanks in advance everyone. :)

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Calculating fourier Series

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