Well, your numerator appears to have an addition sign that shouldn't be there. When I use the ratio test, I like to split the fraction into two, it's significantly easier to see what cancels out in this form. So: $lim_{n \rightarrow \infty} \Large|\frac{a_{n+1}}{1} \cdot \frac{1}{a_n}|$
$a_n$ is just going to be your general term. To find $a_{n+1}$, plug in n+1 into every instance of the variable n, in your general term. The key to simplifying what is inside the absolute values, to easily find the limit, is being proficient with exponents.