[Calculus] Sequence Limits: n -> infinity (n/n^n)(Use Sandwich Rule?)

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SUMMARY

The limit of the sequence defined by a_n = n!/n^n as n approaches infinity is 0, as n^n grows significantly faster than n!. To apply the Sandwich Rule, one must find two bounding functions for n!/n^n. The expression can be expanded to (n/n)*((n-1)/n)*((n-2)/n)*...*(3/n)*(2/n)*(1/n), which suggests that each term approaches 0. Thus, the limit can be established using appropriate bounding functions.

PREREQUISITES
  • Understanding of limits in calculus
  • Familiarity with factorial notation and growth rates
  • Knowledge of the Sandwich (Squeeze) Theorem
  • Basic algebraic manipulation of sequences
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  • Study the Sandwich Theorem in detail to understand its applications
  • Learn about the growth rates of factorials versus exponential functions
  • Explore examples of limits involving sequences and series
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Students studying calculus, particularly those focusing on sequences and limits, as well as educators looking for examples of the Sandwich Rule in action.

raaznar
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Homework Statement


Use sandwich Rule to find the limit lim n> infinity (a_n) of the sequences, for which the nth term, a_n, is given.


Homework Equations


^{lim}_{n\rightarrow∞}\frac{n!}{n^{n}}


The Attempt at a Solution


I know by just looking at it, n^n Approaches infinity much faster than n! which results in limit approaching 0, which is the answer. But the question says to use Sandwich Rule? I don't know which 2 functions to use to bound n!/n^n between? Usually if there was a sin function, I could start with it between -1 and 1. But I don't know where to start for this question?
 
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raaznar said:

Homework Statement


Use sandwich Rule to find the limit lim n> infinity (a_n) of the sequences, for which the nth term, a_n, is given.

Homework Equations


^{lim}_{n\rightarrow∞}\frac{n!}{n^{n}}

The Attempt at a Solution


I know by just looking at it, n^n Approaches infinity much faster than n! which results in limit approaching 0, which is the answer. But the question says to use Sandwich Rule? I don't know which 2 functions to use to bound n!/n^n between? Usually if there was a sin function, I could start with it between -1 and 1. But I don't know where to start for this question?


Expand it. n!/n^n=(n/n)*((n-1)/n)*((n-2)/n)*...*(3/n)*(2/n)*(1/n). Does that give you any ideas?
 

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