Complex fourier series question

wo83
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Homework Statement


What is the fundamental period of f(x) = eax+ibx where a, b are real numbers greater than zero? Find the Fourier series for f(x).

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The Attempt at a Solution


I am able to find the Fourier series for trig based functions but am not sure how to start this one. I was wondering if someone could give me a hint as to how to go about tackling it. My guess would be I have to simplify the function using euler's formula and then go about finding the series in the normal way.

Any hints anyone could offer on this would be greatly appreciated. Thanks
 
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nobody have any ideas?
 
You might use the complex form of the FS. For a function of period 2p:

f(x) = \sum_{-\infty}^{\infty} c_n e^{\frac{in\pi x}{p}}

where

c_n = \frac 1 {2p}\int_{-p}^p f(x) e^{-\frac{i n \pi x}{p}}\, dx
 
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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