Lightning question before the test : )

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How can I show that the sequence { 4^(n)/n! }

converges to zero (by squeeze theorem)??

Thank you! : )
 
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frasifrasi said:
How can I show that the sequence { 4^(n)/n! }

converges to zero (by squeeze theorem)??

Thank you! : )

If the Squeeze Theorem is required as part of the proof, how about comparing

\frac{4^{n}}{n!} < \frac{4^{n}}{n^{n}} (for n > 1)

and showing that the latter goes to zero as n--> infinity?
 
Minor correction, but the "for n > 1" part isn't correct. You can find the correct value, or just say sufficiently large n.
 
as n->infinity n^n>n! so \frac{4^n}{n!} &gt; \frac{4^{n}}{n^{n}}.

I think probably the idea being expressed was to use a constant in the denominator instead of n. \frac{4^n}{8^n}. (or any constant^n in the denominator where the constant>4)

\frac{4^n}{n!}&lt; \frac{4^n}{8^n} for large enough n.
 
Last edited:
Gib Z said:
Minor correction, but the "for n > 1" part isn't correct. You can find the correct value, or just say sufficiently large n.

Whoops! Quite so -- I was only looking at the denominators. That needs to be n > 2 , doesn't it? (n=3 works...)
 
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