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Homework Help: Where to start with laplace

  1. Dec 26, 2005 #1
    for the following question:
    let f(t)=t^2. derive L(f) from L(1)

    my problem:
    i have no clue where to start...
     
  2. jcsd
  3. Dec 26, 2005 #2
    You need to apply the "frequency division" rule :

    [tex]{ \cal L} \{ tf(t) \} = (-1) F^{'}(s)[/tex]

    [tex]{ \cal L} \{ t^nf(t) \} = (-1)^n F^{(n)}(s)[/tex]

    where

    [tex]{ \cal L} \{ f(t) \} = F(s)[/tex]

    and in this case

    [tex]f(t) = 1[/tex]

    marlon

    edit : all rules can be found here
     
    Last edited: Dec 26, 2005
  4. Dec 28, 2005 #3
    wow!!! thank you very much!!!
     
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