Someone Please Check Where I Went Wrong

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SUMMARY

This discussion revolves around solving the differential equation dy/dt = -y + t^2 using the Laplace Transform. The user initially derived the inverse Laplace Transform as y = t^2 - e^-t, but the correct solution is y = t^2 - 2t + 2 - e^-t, as stated in the reference book. The error occurred during the partial fraction decomposition, where the user failed to distribute correctly, leading to an incomplete solution. The correct approach involves using the form A/(s+1) + (Bx+C)/s + (Dx+E)/(s^2) + (Fx+G)/(s^3) for accurate decomposition.

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  • Study the method of Laplace Transforms for solving linear differential equations.
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ColdFusion85
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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??
 
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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?
 
nevermind, got it.
 

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