Hello, I am looking at the following series:
sum, n=1 to infinity
{n^3} / e^n
using the ratio test, we get to:
{(n+1)^3} / en^3
however I cannot understand the final step which goes to 1/e which less than 1, so proves convergency.
Can someone please show me how it goes from :
{(n+1)^3} / en^3
to
1/e
Thanks kindly.