I'm trying to prove that $\lim_{n\to \infty}{\left(1+\frac{1}{n^2}\right)^{n^3}}=+\infty$ using the fact that if $b_n\ge a_n$ eventually, and $\lim_{n\to \infty}{a_n}=+\infty$, then $\lim_{n\to \infty}{b_n}=+\infty$, where $b_n:=n^n$.
I'm struggling to show that $b_n\ge a_n$ by induction. Is this a good method? If so, what would be the best way to proceed. Thank you in advance.
Answer
Using my comment: for almost all $\;n\in\Bbb N\;$ , we have that (since $\;e=2.7...\;$)
$$2.5\le\left(1+\frac1{n^2}\right)^{n^2}\le3\implies\left[\left(1+\frac1{n^2}\right)^{n^2}\right]^n\ge(2.5)^n\xrightarrow[n\to\infty]{}\infty$$
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