Find Limit: Evaluate \frac{n}{(n!)^{\frac1n}}

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Discussion Overview

The discussion focuses on evaluating the limit \(\lim_{n\rightarrow\infty}\frac{n}{(n!)^{\frac1n}}\), exploring different methods for approaching the problem, including Stirling's approximation and alternative techniques.

Discussion Character

  • Exploratory
  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant presents the limit to be evaluated and reformulates it as \(\lim_{n\rightarrow\infty}\frac{n}{\sqrt[n]{n!}}\).
  • Another participant introduces Stirling's approximation, suggesting it leads to the limit being \(e\).
  • Some participants express a desire to find a solution without using Stirling's approximation, indicating a preference for alternative methods.
  • A later reply argues that while Stirling's approximation simplifies the problem, transitioning from a sequence to a function is problematic due to the factorial in the denominator.
  • It is noted that expressing \(n!\) as \(\Gamma(n+1)\) does not resolve the issue of dealing with discrete values of \(n\).

Areas of Agreement / Disagreement

Participants do not reach a consensus on the preferred method for solving the limit, with some advocating for Stirling's approximation while others seek alternative approaches.

Contextual Notes

The discussion highlights the challenges of evaluating limits involving factorials and the implications of using approximations versus exact methods.

Ali 2
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Hi ,

Evaluate the following limit :

[tex]\lim_{n\rightarrow\infty}\frac{n}{(n!)^{\frac1n}}=\lim_{n\rightarrow\infty}\frac{n}{\sqrt[n]{n!}}[/tex]
 
Last edited:
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I know about that .. the solution will be obtained easily by that method ..



but.. could you solve the question without stirling's approximation ?
 
Last edited:
Ali 2 said:
I know about that .. the solution will be obtained easily by that method...but...could you solve the question without stirling's approximation ?

I'm afraid Stirling's approximation provides the simplest approach.Keep in mind that u've to compute the limit of a sequence and u cannot make the transition to a function,due to a factorial in the denominator.Of course,that factorial can be put under the form
[tex]n!=\Gamma(n+1)[/tex]
,but that won't do you any good,since it still involves discrete values for "n".

Daniel.
 

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