proof that $\lim_{x \to \infty} exp(x) = \infty $ ( no hopital proof)

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just tell me please if my idea correct is

$$\exp(x) = \sum_{k=0}^{n} \frac{x^k}{k!} > \frac{x^n}{n!} $$

let $x > R= (n+1)!$ $\Rightarrow $ $$\frac{x^n}{n!}>\frac{R^n}{n!} >\frac{R}{n!}>\frac{(n+1)!}{n!}= n+1 $$

let $n_{0} \in \mathbb{N}$ so that n>$n_{0}$ for a big $n_{0}$

for all M >0 let s choose R = M!

then for all $x > R =(n+1)!$ there is a $M =(n+1)$ so that $\exp(x) > M$

$ \Rightarrow \lim_{x \to \infty}\exp(x) = \infty $

is that correct ?