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
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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