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# Radius of convergence question Watch

1. I a stuck on trying to find the radius of convergence for:
sum for n=1 to infinity of:
(3n)!(z+i)^n/((2n)!(n+1)^n)
Do you have to use both the ratio test and nth root test? Is it possible to us both tests at the same time?
2. (Original post by Harriettttttt1)
I a stuck on trying to find the radius of convergence for:
sum for n=1 to infinity of:
(3n)!(z+i)^n/((2n)!(n+1)^n)
Do you have to use both the ratio test and nth root test? Is it possible to us both tests at the same time?
Latex turns this into

Is that what you meant?
3. (Original post by atsruser)
Latex turns this into

Is that what you meant?
yes
4. (Original post by Harriettttttt1)
yes
I think that the root test works for this. Have you tried it?

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