Complex Analysis - Contour Integration

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SUMMARY

The discussion centers on the evaluation of the integral \(\oint_{\Gamma} \dfrac{3z - 2}{z^2 - z} dz\) over the contour \(\Gamma = \{ z \in \mathbb{C} | |z| + |z-1| = 3 \}\). The lecturer concluded that the integral evaluates to \(6\pi i\) using Cauchy's residue theorem. The key takeaway is that only the poles within the contour, specifically at \(z=0\) and \(z=1\), contribute to the integral's value. Understanding the computation of residues is essential for grasping this evaluation.

PREREQUISITES
  • Complex analysis fundamentals
  • Cauchy's residue theorem
  • Contour integration techniques
  • Residue computation methods
NEXT STEPS
  • Study Cauchy's residue theorem in detail
  • Learn how to compute residues for simple poles
  • Explore different types of contours in complex analysis
  • Practice evaluating integrals using contour integration
USEFUL FOR

Students and professionals in mathematics, particularly those focusing on complex analysis, as well as educators teaching contour integration techniques.

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?
 

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