Inverse Laplace Transform and Branch Points

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Homework Statement



Find the inverse Laplace Transform of \frac{1}{s}\frac{\sqrt{s}-1}{\sqrt{s}+1}

Homework Equations



The complex inversion formula (well known)

The Attempt at a Solution



The first thing is finding singularities and branch points and so on. From the \frac{1}{s} part of the function, it seems as though s=0 is a simple pole (a pole of order one). However, it is known that each \sqrt{s} has a branch point at s=0. Therefore the function has a branch point at s=0. Performing a substitution s=\frac{1}{t} into \sqrt{s} shows that the point at infinity is a branch point as well. I am about to start using the complex inversion formula, but am not sure about whether I have taken into account all the possible branch points/singularities.

Any ideas guys?
 
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Isn't s=1 a singular point? That is, what is the multi-valued square root of 1?
 
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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