Analyzing Singularities at z=2 & -1/3

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Homework Statement



I have been asked to state the precise nature of the singularities at z=2 and z=-1/3 in
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Homework Equations



I know the laurent series is given by
vymfz4.png


The Attempt at a Solution



I think I need to expand the series out into a laurent series around z=2 and z=-1/3 but I am really stuck on how to do this and would really appreciate a bit of help! From some examples I have seen I need to manipulate the denominator into a known series and then expand this but I am unsure of how to do that. Thanks
 
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You don't need to expand anything. You just need to review the definition of a pole of order n.
 
I know I don't have to but I thought that a laurent expansion was another way to find out the nature of a singularity, like what the order of the pole was, and I just wanted to try and get a grasp of this technique as well and get the same answer for both techniques
 
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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