- #1
iRaid
- 559
- 8
Homework Statement
Well I have a series that I solved one way, but my professor solved another and I'm wondering if my way is ok.
[tex]\sum\limits_{n=1}^\infty \frac{(-5)^{2n}}{n^{2}9^{n}}[/tex]
Homework Equations
The Attempt at a Solution
Alright well I started out by changing it to:
[tex]\sum\limits_{n=1}^\infty \frac{1}{n^{2}}(\frac{(-5)^{2n}}{9^{n}})=\sum\limits_{n=1}^\infty \frac{1}{n^{2}}(\frac{25}{9})^{n}[/tex]
So I concluded since the second part is a geometric series with r>1, it's divergent.
Is this allowed?