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Homework Help: Maths help on Fourier Expansion

  1. Sep 22, 2011 #1
    Dear all,

    Iam just wondering whether the term 1/a can be expanded using Fourier expansion. If it does, please let me know how to to do this.

    Thank for any kind help.
     
  2. jcsd
  3. Sep 22, 2011 #2

    HallsofIvy

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    Re: need help about Fourier Expansion

    What do you mean bu "the term 1/a"? Normally, we expand functions in Fourier series, not numbers. Of course, we can think of f(z)= 1/a as the constant function. In that case, the Fourier series is simply (1/a)+ 0 sin(z)+ 0 cos(z)+ ...

    If you mean f(z)= 1/z, then, yes, you can find a Fourier series for 1/z using the standard formulas. It will not converge at z= 0, of course.
     
  4. Sep 22, 2011 #3
    Re: need help about Fourier Expansion

    How about f(x) = (1 - x/a), what would be the solution after Fourier expansion?
     
  5. Sep 22, 2011 #4

    LCKurtz

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    Any constant is a finite Fourier series with all the sine and cosine terms having 0 coeifficients. There is nothing to calculate.
     
  6. Sep 22, 2011 #5

    LCKurtz

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    Re: need help about Fourier Expansion

    Your f(x) needs to be periodic to have a FS.
     
  7. Sep 22, 2011 #6

    Mark44

    Staff: Mentor

    Moderator's note: I copied several posts from the thread that was started in the Mathematics technical section.
     
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