This question is similar to another one I've posted
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so I let
And I used a closed semicircle which contains of radius R.
Let
I let: and
By Jordan's Lemma, as
By the Cauchy Residue Theorem
Now I use the following theorem to evaluate the theorem
If is entire and is analytic everywhere except but is entire.
The
However, I can't get the following to evaluate correctly
I am having troubles with . None of the identities in my text book seem to help.