Question

Evaluate\oint_{c}^{}\frac{dz}{z^{2}+1}where c is the circle | z | = 4.

22 Mar 2023
Answer :
Word Count : 353

To evaluate the integral, we will use the Cauchy Integral Formula, which states that for a function f(z) that is holomorphic (complex differentiable) inside and on a simple closed contour C, and a point a inside C:

∮[C] (f(z)/(z - a)) dz = 2πi * f(a)

The given integral is:

∮[C] (dz/(z^2 + 1))

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