Hi, I don't really need help with a problem, just having some troubles understanding something. Find the interval of convergence of the series sigma[n=0,inf] (x-1)^n/n^3 by the root test I got that |x-1|<1 and that 0<x<2 I than have to plug in these values (0 and 2) to see if the series converges or diverges at these endpoints... I however am confused by this. If we set x = 0 or x = 2 wouldn't the root test give us 1 and the root test states that if the limit equals one than the series converges. So what's the need of testing the end points? Like I know we have to just am not really sure why because than the root test would give us 1... I never understood why we test the end points and just sort of did so just because I was told we had to and was wondering if someone could explain this to me. I hope someone can clear up this confusion for me. Thanks for any help!