Question

Find the interval of convergence for
\[
\sum_{n=1}^{\infty }\, \frac{x^n}{n3^n}
\]

Answer 1

I get to abs(x/3) but where do I go from there?

Answer 2

you need ...\[\left|\frac{x}{3}\right|<1\]

Answer 3

so is the interval between x=0 and x=3?

Answer 4

no

Answer 5

I did -3<x<3 on my test but it was marked off?

Answer 6

that is because it is not correct ;)

Answer 7

you need to check the endpoints for convergence

Answer 8

k thanks