hi guys I was asked to find the radius of convergence of the
hi guys, I was asked to find the radius of convergence of the series (n^n / n!) (x^n) (n=1 to and n goes to infinity). I used the ratio test for this problem but did something very wrong and ended up with lim n-> infinity n+1 which is not convergent at all. Would anyone please be kind enough to show me the steps on how to solve this problem, thank you very much in advance, I really appreciate your taking the time to help me out!
Solution
RAtio test
dont use ration test as their power is n so use root test :
lim n-> infintiy (Tn)1/n
: n/ (n!)1/n * x : lim turns out 0
: | Radius * 0 | = 1
radius of convergence : infinity !!!
