[tex] \sum_{r=1}^{\infty} \frac{r!}{3^{r^{2}}} [/tex](adsbygoogle = window.adsbygoogle || []).push({});

My solution:

[tex] \frac{3^{r^2}}{r!} > r^2 [/tex]

So [tex] \frac{r!}{3^{r^2}} < \frac{1}{r^2} [/tex]

So as 1/r^2 converges, it converges by comparison test.

This was in my exam today, I messed up a lot leading up to it. But the question said I could use any test in general to work this out.

It was work 6 marks which is quite a bit so is my solution okay ?

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# Homework Help: Series test ?

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