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: An inverse fourier transform

  1. Jan 9, 2012 #1
    1. The problem statement, all variables and given/known data
    (part of a problem)
    Find the inverse fourier of F(w) = (3jw+9)/((jw)^2+6jw+8)
    where w is the angular frequency, w=2pi * f = 2*pi/T

    2. Relevant equations
    The fourier transfrom and its properties i guess.
    Also the exponential FT common pair exp(-at)u(t) <-> 1/(jw+a)
    where exp is the exponential function and u(t) the unit step function

    3. The attempt at a solution
    I factored out the denominator in a hope that the 3jw+9 would cancel out with a possible root of jw=-3 , but the roots are -2 and -4.
    I've been trying to seperate F into a product of easy transformable parts, to take advantage of the convolution property : x(t) [convolve] f(t) = X(w)F(w) , but i cant get rid of the nominator to apply the exponential fourier pair.
    Any hints?
  2. jcsd
  3. Jan 9, 2012 #2
    If the nominator was a constant, i could break it into simple fractions.
    Can you do it if it's not a constant?
  4. Jan 9, 2012 #3
    Ah,nevermind, you can.
    case closed.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook