1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Half-Range Fourier Series

  1. Dec 30, 2008 #1
    1. The problem statement, all variables and given/known data

    Question: Find the half-range Fourier sine series for the function f(t) = t sin(t)

    Problem: According to all the examples I have gone through, they all have a limit when asking for the half-range. However, my teacher, in the question posted above, has not specified any limits. Is this a typing error? If not, can you please nudge me in the right direction.

    2. Relevant equations

    3. The attempt at a solution

    None yet. I'm under the impression that question may have been typed wrong.
  2. jcsd
  3. Dec 30, 2008 #2
    I think -pi to pi are standard ...
    Currently, it is an even function, I can suggest making it odd t*cos(t) and finding fourier series from 0 to 2pi.
  4. Dec 30, 2008 #3
    Ok here is what I gather so far:

    I am looking for the sine half-series, which is bn.Sin(nt) from the fourier series.


    bn = I{t.sin(t).sin(nt)} between 0 and 2pi

    ... which goes to ...

    bn = I{t.sint(1+n)} between 0 and 2pi?

    Is that correct?

    EDIT: ... which gives me 0. I think I misunderstood.

    Reading your suggestion again, you have changed t.sin(t) to t.cos(t)... Why is that? I can see we get an odd function (odd . even) but not sure how we came about the change...

    Apologies in advance if I sound retarded, but 2 lectures on fourier was no way near enough in my opinion.
    Last edited: Dec 30, 2008
  5. Jan 5, 2009 #4
    Any ideas?
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Half-Range Fourier Series