Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Trignometric Polynomial complex form

  1. Sep 7, 2011 #1
    Hi,
    I'm trying to learn Fourier transforms by myself. I'm a bit confused about how the trignometric polynomial complex form was derived. I'm refering to this:

    http://en.wikipedia.org/wiki/Trigonometric_polynomial

    Now, I haven't taken complex analysis so I only know the basics. I used Euler's formula and got that far but I'm not sure what to do next.

    Thanks
     
  2. jcsd
  3. Sep 7, 2011 #2

    micromass

    User Avatar
    Staff Emeritus
    Science Advisor
    Education Advisor
    Insights Author

    Substitute

    [tex]\cos(nx)=\frac{e^{inx}+e^{-inx}}{2}, ~\sin(nx)=\frac{e^{inx}-e^{-inx}}{2i}[/tex]

    in the series and rearrange everything. This should give you the required form.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Trignometric Polynomial complex form
  1. Complex polynomials (Replies: 2)

  2. Complex polynomial (Replies: 2)

Loading...