How to prove that this two functions have simple poles:
at
at
where k is an integer
Regards.


I'm not sure I understood your definition of a 'simple pole'. Is not a pole commonly defined as the values ofsuch that the denominator is zero? And perhaps by simple, you mean that the pole has multiplicity one?
For example, the first functionwould have a pole when
, or equivalently
. Then
certainly is a pole, but since
is periodic, there most certainly are other poles also.