I'm not able to show that this expression:
can be written
Partial fraction decomposition of gives
I found by plugging into wolframalpha.
But I can't find a way to from either.
Any hints or things to try?
I have tried to write
then multiplying through by the denominator gives
and then evaluate at such that it reduces to
But that gives one equation with 2 unknowns and thus appear to be a dead end!