Proving the Limit of an Expression: \frac{n^n}{n!}

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ercagpince
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Homework Statement


what is the limit of this expression?

[tex]lim_{n\rightarrow\infty}\frac{n^n}{n!}[/tex]

Homework Equations


The Attempt at a Solution


I tried to make it look like [tex]\frac{x^n}{n!}[/tex] and also tried to apply the sandwich theorem, but got nothing logical.
Probably the limit is [tex]\infty[/tex], still I want to prove it mathematically.
 
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You could take the log and use Stirling's approximation on the factorial.
 
ercagpince said:
Could you show it explicitly?

If you mean show the details, Isn't that your job? Did you look up Stirling's approximation? Or do you mean do it without Stirling's formula?
 
if you take the stirling's approximation there is no need to take log of the term on numerator.
that why i asked that.
 
ercagpince said:
if you take the stirling's approximation there is no need to take log of the term on numerator.
that why i asked that.

Right, if you use the form n!~(n/e)^n. I was thinking of ln(n!)~n*ln(n)-n