Prove that $r^n/n!$ converges where $n\ge r$ The answer is in the title of the question.  I need to show it converges to 0 and $r>0$.  I am sorry if this is a bad question, I'm having trouble explaining it.  So essentially this Do the $\lim_{n\to inf}\frac{r^n}{n!}=0.$

I asume that you want to prove: 
$$\lim_n\displaystyle\frac{r^n}{n!}=0 $$
and $r>0$ is fixed.
Let $N$ be an integer number such that $N> r$. Then for $n>N$ the following holds:
$$\displaystyle\frac{r^n}{n!}=\displaystyle\frac{r}{1}\cdots\displaystyle\frac{r}{N-1}\displaystyle\frac{r}{N}\cdots\displaystyle\frac{r}{n}<\displaystyle\frac{r}{1}\cdots\displaystyle\frac{r}{N-1}(\displaystyle\frac{r}{N})^{n-N}   $$
you have that $\displaystyle\frac{r}{1}\cdots\displaystyle\frac{r}{N-1}$ is a constant and $\displaystyle\frac{r}{N}<1$. Try to conclude. 
