Does the denominator become larger faster

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SUMMARY

The discussion focuses on the convergence of the sequence defined by a_{n} = n!/n^n. Participants analyze the limit as n approaches infinity, specifically comparing the growth rates of the numerator and denominator. The conclusion drawn is that the denominator n^n grows significantly faster than the numerator n!, leading to the limit approaching zero, thus confirming that the sequence converges to zero.

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  • Understanding of factorial notation and properties
  • Knowledge of limits and convergence in sequences
  • Familiarity with asymptotic analysis
  • Basic calculus concepts, particularly L'Hôpital's Rule
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Students and educators in mathematics, particularly those studying calculus and sequences, as well as anyone interested in understanding the behavior of factorial growth compared to exponential functions.

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Homework Statement


Determine if convergent or divergent. Determine limit if convergent.

Homework Equations


[itex]a_{n} = \frac{n!}{n^n}[/itex]

The Attempt at a Solution


As per the hint, i use 1/n to compare.

however, how is this statement true:

[itex]\lim_{x\to\infty} \frac{n!}{n^n} <= \lim_{x\to\infty} \frac{1}{n}[/itex]??

does the denominator become larger faster than the numerator making it a smaller number than the 1/n?
 
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whatlifeforme said:

Homework Statement


Determine if convergent or divergent. Determine limit if convergent.

Homework Equations


[itex]a_{n} = \frac{n!}{n^n}[/itex]

The Attempt at a Solution


As per the hint, i use 1/n to compare.

however, how is this statement true:

[itex]\lim_{x\to\infty} \frac{n!}{n^n} <= \lim_{x\to\infty} \frac{1}{n}[/itex]??

does the denominator become larger faster than the numerator making it a smaller number than the 1/n?

Think about it. E.g. 3!/3^3 is less than 1/3. Why is that? That's (1*2*3)/(3*3*3).
 
dick said:
think about it. E.g. 3!/3^3 is less than 1/3. Why is that? That's (1*2*3)/(3*3*3).

update: nevermind.
 

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