Find the value of x of the fourier series defined by

Zaent
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Homework Statement


upload_2015-4-29_4-13-1.png


Homework Equations


upload_2015-4-29_4-14-32.png


The Attempt at a Solution


http://imgur.com/7TRWjBg

I don't really get what it's asking. I don't know how to define a Fourier series when the boundaries for X are between non-multiples of Pi. On top of that, it has one boundary that has 4<x<2Pi. How can it be between 4 and 2 Pi? My attempt at a solution seems like it has to be totally the wrong way to go about it
 
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Zaent said:

Homework Statement


View attachment 82737

Homework Equations


View attachment 82738

The Attempt at a Solution


http://imgur.com/7TRWjBg

I don't really get what it's asking. I don't know how to define a Fourier series when the boundaries for X are between non-multiples of Pi. On top of that, it has one boundary that has 4<x<2Pi. How can it be between 4 and 2 Pi? My attempt at a solution seems like it has to be totally the wrong way to go about it

Your function is defined between ##0## and ##2\pi##, with a couple of jump discontinuities. So you have the given ##f(x)## and its FS ##S(x)##. Do you know what the Dirichlet conditions are? Look in your book for that. It will tell you something about when ##f(x) = S(x)## and when it doesn't. This problem does not involve calculating the FS.
 
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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