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Homework Help: Laplace transformation

  1. Dec 11, 2008 #1
    How can I transform

    [tex]F(s) = \frac{1}{(s-2)^2}[/tex]

    ?

    I cannot see that any of the functions in my table is useful...

    j0cxhy.jpg
     
  2. jcsd
  3. Dec 11, 2008 #2

    gabbagabbahey

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    Use the third one in the list along with the "frequency shifting rule": [tex]\mathcal{L}^{-1}[F(s-\alpha)]=e^{\alpha t}\mathcal{L}^{-1}[F(s)][/tex]
     
  4. Dec 11, 2008 #3

    HallsofIvy

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    Actually, it's the second one in the list: the Laplace transform of 1/t is 1/s2. I think gabbagabbahey was counting the heading. Also note that gabbagabbahey's "frequency shifting rule" is implied in the third, the Laplace transform of eat is 1/(s-a) which is just the laplace transform of 1/t "shifted" by a.
     
  5. Dec 11, 2008 #4

    gabbagabbahey

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    Actually I meant the third (with n=1 of course)---but certainly the second is a little more straightforward!:smile:
     
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