what is value of $\lim_{n\to\infty} n^{-2}e^{(\log(n))^a}$?

Question

What is value of $\displaystyle\lim_{n\to+\infty} n^{-2}e^{(\log(n))^a}$, where $a > 1$? I tried l'Hospital's rule but it gets complicated.

Answer 1

$n^{-2}e^{(\log(n))^a} = e^{(\log(n))^a - 2 \log(n)}$. If $a$ is a constant greater than $1$ then $(\log(n))^a$ will dominate compared to $2 \log(n)$, so this expression will also go to infinity as $n$ goes to infinity.

Answer 2

Hint: Consider taking the logarithm.