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Question

Math 6210 • Real Analysis

2005 • Question 10

Let \(f\) be a function holomorphic in \(\mathbb C-\{0,2\}\). Assume that:

(i) \(0\) and \(2\) are first order poles of \(f\);

(ii) that \(f\) is bounded for \(|z|\ge R\) for sufficiently large \(R\);

(iii) the integral \(\int _\gamma f(z)\,dz\) is equal to:

a) \(2\pi i\) if \(\gamma \) is a positively oriented circle of radius \(1\) centered at \(0\);

b) \(0\) if \(\gamma \) is a positively oriented circle of radius \(3\) centered at \(0\).

Determine the function \(f\).

Raw LaTeX

Let \(f\) be a function holomorphic in \(\mathbb C-\{0,2\}\). Assume
that:

(i) \(0\) and \(2\) are first order poles of \(f\);

(ii) that \(f\) is bounded for \(|z|\ge R\) for sufficiently large \(R\);

(iii) the integral \(\int_\gamma f(z)\,dz\) is equal to:

a) \(2\pi i\) if \(\gamma\) is a positively oriented circle of radius \(1\) centered
at \(0\);

b) \(0\) if \(\gamma\) is a positively oriented circle of radius \(3\) centered at \(0\).

Determine the function \(f\).