Answer

问题及解答

求下列极限

Posted by haifeng on 2020-12-22 09:44:35 last update 2020-12-22 09:48:11 | Edit | Answers (1)

1.    $\lim\limits_{n\rightarrow\infty}\dfrac{\ln(n!)}{n^2}$

 

 

2.    $\lim\limits_{n\rightarrow\infty}\dfrac{\ln(n!)}{n}$

1

Posted by haifeng on 2020-12-22 09:47:40

由于 $n! < n^n$, 故对于 $n > 1$, 有

\[
0 < \frac{\ln(n!)}{n^2} < \frac{\ln(n^n)}{n^2}=\frac{n\ln n}{n^2}=\frac{\ln n}{n}
\]

由于 $\lim\limits_{n\rightarrow\infty}\dfrac{\ln n}{n}=0$, 故 $\lim\limits_{n\rightarrow\infty}\dfrac{\ln(n!)}{n^2}=0$.