Complex Analysis - Contour Integration

QuantumJG
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In a lecture today we evaluated a integral:

\oint_{\Gamma} \dfrac{3z - 2}{z^2 - z} dz

Where,

\Gamma = \{ z \in \mathbb{C} | |z| + |z-1| = 3 \}

Our lecturer evaluated it to be 6πi

I sort of understood how he did it, but he really rushed through his steps.
 
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So what is you specific question? You have two poles in your integrand z=0 and z=1, you use Cauchy's residue theorem to do the integral and you need to compute residues. However ONLY the poles that are inside the contour are counted.

Can you draw the contour?
 
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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