1. Limited time only! Sign up for a free 30min personal 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!

Homework Help: Fourier series-desperately needing help

  1. Sep 13, 2007 #1
    fourier series--desperately needing help

    1. The problem statement, all variables and given/known data


    http://www.exampleproblems.com/wiki/index.php/FS1
    2. Relevant equations

    in the a[tex]_{n}[/tex] on the fifth equal sign, why was (-1 ^n)? how did he arrive at that equation?


    have mercy..
    its our quiz today
    and i really have a hard time on fourier

    3. The attempt at a solution
     
  2. jcsd
  3. Sep 13, 2007 #2
    cos (\pi n) for n = even integer is equal to 1,
    while for n = odd inetger, it is equal to -1.
    The function (-1)^n has the same property.
    Since n is an integer and must be either even or odd,
    we can replace cos (\pi n) with (-1)^n .
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook




Loading...