[Math] Find and prove the limit of $X_n=$ $\frac {n^{100}}{1.01^n}$

calculuslimitssequences-and-series

I have to find and prove the limit of the sequence $X_n=$ $\frac {n^{100}}{1.01^n}$

What is the easier way?

I tried to use Bernoulli's inequality to say lim$\frac {n^{100}}{1.01^n}$ = lim$\frac {n^{100}}{(1+1/10)^n}$ and $ (1+1/10)^n \geq 1+n(1/10).$ But I could get anything.
I think another way is to use the Squeeze Theorem but I have not could find the correct sequences.

Any Ideas?

I only can use the definition, Squeeze Theorem, the Bernoulli's inequality or using operations to reduce the sequence.

Best Answer

We have $$\frac {n^{100}}{1.01^{n}} = \left(\frac{n}{1.01^{n/100}}\right)^{100} $$ By Bernoulli's inequality on the inside quantity, $$\begin{align}\left(\frac{n}{\left(1+\frac{1}{100}\right)^{n/100}}\right)^{100} &\leq \left(\frac{n}{1 + \frac{1}{100}\cdot\frac{n}{100}}\right)^{100} \\ &< \left(\frac{n}{\frac{n}{10000}}\right)^{100} \\ &= 10000^{100} \end{align}$$

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