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Homework Help: Inverse Laplace

  1. Nov 7, 2008 #1
    1. The problem statement, all variables and given/known data
    [tex]F(s) = \frac{s^2 + 1}{s^2 + 4s + 3}[/tex]
    Find the inverse laplace transform?

    3. The attempt at a solution
    Since the nominator's degree is not smaller that the denominator, i have to do the long division before doing the inverse laplace.

    [tex]F(s) = \frac{- 4s - 2}{(s+1)(s+3)} + 1[/tex]

    I can get the inverse laplace for the first term. However, I was stopped at L-1{1}. Need help. Thank you.
  2. jcsd
  3. Nov 7, 2008 #2


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    Hint: What is [tex]\int_{0^-}^{\infty} \delta (t) e^{-st}dt[/tex] ? (where [itex]\delta[/itex] is the dirac delta function)
  4. Nov 7, 2008 #3


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