This question is similar to another one I've posted
so I let
And I used a closed semicircle which contains of radius R.
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.
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.