Originally Posted by

**2complex4me** Hello everyone,

Firstly, I am new and my apologies if my questions are buried somewhere in the thread heap already.

I am taking a complex analysis course, and well, its 2complex4me! So here are my questions...

I need to find the radius of convergence of the following complex power series: (so naturally z is in C here).

My apologies for not using nice looking math typeset, but I dont know the code for it.

The mth order Bessel function:

Jm(z) = sum[ {((-1)^n) ((z/2)^(m+2n))} / {n!(n+m)!} , n=0, n=infinity ]

Also

sum[ z^n!, n=0, n=inf ]

And

sum[ (n+a^n)z^n, n=0, n=inf ]

I will undoubtedly have more questions as I progress in the course, but if someone can help me out here, I would be very greatful!

Thank you, Damian.