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Math Help - Need help for Laplace transform

  1. #1
    Member moonnightingale's Avatar
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    Need help for Laplace transform

    What is laplace transform of
    exp(-at)u(-t)


    and if laplace of x(t) is 1/s then laplace of dx(t)/dt will be...
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  2. #2
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    Re: Need help for Laplace transform

    The first one looks like a frequency shift. The other one like differentiation. Both transforms can be look upon as trivial, so look them up in a table.
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  3. #3
    Member moonnightingale's Avatar
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    Re: Need help for Laplace transform

    i could not find
    plz give me answer
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  4. #4
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    Re: Need help for Laplace transform

    \displaystyle \begin{align*} \mathcal{L}\left\{e^{at}f(t)\right\} = F(t - a) \end{align*}
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    MHF Contributor chisigma's Avatar
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    Re: Need help for Laplace transform

    If the function is f(t)=e^{- a t}\ u(-t) then fot t>0 is f(t)=0, so that its single side Laplace Tranform is...

    \int_{0}^{+ \infty} f(t)\ e^{- s t} dt =0



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    \chi \sigma
    Last edited by CaptainBlack; December 16th 2011 at 10:22 PM. Reason: minor fix to LaTeX
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