Integration in Frequency Domain

yukari1310
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How to integrate $$\int_{-0.5}^{0.5} {\bigg({\frac{1}{4-2e^{-j2{\pi}f}}}\bigg)}^2 df$$
 
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Homework Statement



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The Attempt at a Solution


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Hello again; must be you forgot how PF homework sections work: you are supposed to make an effort yourself.
In the mean time I do wonder where this comes from and what the problem statement really is: you now seem to be wanting to integrate a complex function over a section of the real axis ?
 
I did try it somewhere else using integration by parts but the function to be integrate just got more complicated as I go on.
I am suppose to find the energy signal of a DTFT [ie X(f)] signal. The range defined is over the principal period of the DTFT signal.
 
Isn't the energy a real number ?
 
Yeah? So can you give me some hints on how to integrate the complex function?
 
I would think a rather obvious substitution would be u= 4- 2e^{j2\pi f}. Did you try that? What do you get?
 
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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