Limit tends to infinity problem.

Question

Here is a problem about limit tends to infinity.I have given an answer.Please let me know,if this is correct

Answer 1

The answer is correct. Just write $$\lim_{n\to \infty} \frac{3^n - 3^{-n}}{3^n + 3^{-n}}= \lim_{n\to \infty} \frac{3^n}{3^n}\cdot \frac{1 - 3^{-2n}}{1 + 3^{-2n}} = 1$$ and add that $\lim_{n\to \infty} 3^{-2n} =0$. I personally would avoid to write something like $3^{-\infty}$.

Answer 2

Yes your answer is correct. Any integer divided by zero is infinity except zero.

Either it's 1/0 or -2/0.