- #1
cragar
- 2,552
- 3
Homework Statement
Determine the order of the poles for the given function.
[itex] f(z)=\frac{1}{1+e^z} [/itex]
Homework Equations
The Attempt at a Solution
I know if you set the denominator equal to zero
you get z=ln(-1)
But if you expand the function as a geometric series ,
[itex] 1-e^{z}+e^{2z}... [/itex]
I don't see how there is a pole in the geometric series expansion , there is no division by zero. [/B]