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Need help with an integral: Laplace Transform of a chirp

  1. Apr 28, 2008 #1
    I am trying to find the Laplace Transform of a chirp:
    Essentially this requires evaluating an integral between zero and infinity of:

    (exp(s*t))*sin(t^2) with respect to t where s is the parameter (Laplace space frequency).

    Any help or advice or a redirect to some useful link would be much appreciated.
  2. jcsd
  3. Apr 28, 2008 #2
    TRICK: use Euler's formula [tex] 2sin(x)i=e^{ix}+e^{-ix} [/tex]

    with [tex] \int_{0}^{\infty}dt.e^{at-st}= (s-a)^{-1} [/tex]

    'a' here can be any real or complex number , hope it helps
  4. Apr 28, 2008 #3
    However doesn't the t^2 inside the sine function make the suggested trick invalid?
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