Inverse Transformations of ODEs

kikko
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Homework Statement



F(s) = s/((s-1)(s^2+1))

F(s) = (s/(s^2+4s+5))(e^(-3s))


Homework Equations



Don't believe there are any.

The Attempt at a Solution



Not particularly sure. I can solve ((s-2)(e^-s))/(s^2-4s+3), but seem to be having problems with these.
 
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Are you referring to Laplace transforms?
 
Yes. I started the second by making the bottom more condensed and finding a G(s) separate of F(s), but am stuck here.
 
My advice is to use partial fractions on:
<br /> \frac{s}{s^{2}+4s+5}<br />
and use a look up table.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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