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Homework Help: Someone Please Check Where I Went Wrong

  1. Apr 20, 2005 #1
    This is a Laplace Transform problem. dy/dt = -y + t^2. I formed the inverse laplace transform equation which i verified is correct, then i took partial fraction decompositions and got for a final answer that y = (L inverse) [2/s^3 - 1/(s+1)]. and hence, y = t^2 - e^-t. however the book states that the answer is t^2 - 2*t + 2 - e^-t. where did i go wrong??
     
  2. jcsd
  3. Apr 20, 2005 #2
    Oops, I think it has to be distributed as [tex] \frac{A}{(s+1)} + \frac{(Bx+C)}{s}+ \frac{(Dx+E)}{(s^2)}+\frac{(Fx+G)}{(s^3)}[/tex], doesn't it?
     
  4. Apr 20, 2005 #3
    nevermind, got it.
     
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