For what $x \in \mathbb{R}$ does the series $\sum_{n=0}^{\infty} n!x^{n}$ converge?

92 Views Asked by At

For what $x \in \mathbb{R}$ does the series $\sum_{n=0}^{\infty} n!x^{n}$ converge?

How would you prove this? Does the ratio test apply?

1

There are 1 best solutions below

0
On

Yes, the ratio test applies and yields that it converges for $x=0$ only.

Let me know if you need more details.