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

f(x) = x+1 for -1,x<0

x-1 for 0<x<1

0 for x=0

expand it in an appropriate cosine or sine series

2. Relevant equations

f(x) = a_{0}/2 + [itex]\sum[/itex] [a_{n}cos (n[itex]\pi[/itex]x/p) + b_{n}sin (n[itex]\pi[/itex]x/p)

a_{0}= 1/p [itex]\int[/itex]f(x).dx

a_{n}= 1/p [itex]\int[/itex] f(x)cos (n[itex]\pi[/itex]x/p).dx

b_{n}= 1/p [itex]\int[/itex] f(x)sin (n[itex]\pi[/itex]x/p).dx

3. The attempt at a solution

As there are two functions within this f(x), I am unsure of how to go ahead and do this.

I realise the overall function is odd, therefore would only need to expand the b_{n}part of the Fourier series, however the individual functions are not odd.

How would I go about setting this up?

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# Homework Help: Fourier expansion between two different intervals

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