Find the radius of convergence of the following series
Using the ratio test I get the following:
As far as I can see this converges for all real numbers, but the answer says
Where am I going wrong? Thanks.
I guess I don't.
(All I know is my DE professor is trying to refresh us on the ratio test so that we can learn to solve DEs with power series. I guess I will just hope there's an easier one that doesn't involve e if it comes up on the test. If not, I'll be screwed.)