Using L'hopital's rule in exponential function

[Elsasw]

Is that any way to find a finite value which is not equal to zero using L'hopital's rule in

limit(z=-ia)
exp[-A/(z+ia)]/(z+ia)^2

i kept getting 0/0 after differentiation

Thank you

 

[HallsofIvy]

So your problem is
$$\lim_{z\to -ia}\frac{e^{-A/(z+ ia)}}{(z+ia)^2}$$
?
Instead, write the exponential as a Laurent series around -ia. It should be clear that you will have a "1" as the constant term and so the limit will not exist. This function has a pole of order 2 at z= -ia.

 

[Elsasw]

Thank you very much HallsofIvy...i got what u meant..