Can you be elegant

Calculus Level 3

1 2 lim ω ( ω ! ) 1 ω ω \frac{1}{2}-\displaystyle\lim_{ω\rightarrow \infty}\frac{(ω!)^{\frac{1}{ω}}}{ω} is

can't be determined positive negative 0

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

1 solution

Shivam Jadhav
Feb 19, 2016

By using A M G M AM-GM 1 + 2 + 3 + . . . . + ω ω ( ω ! ) 1 ω \frac{1+2+3+....+ω}{ω}\geq(ω!)^{\frac{1}{ω}} ( ω ) ( ω + 1 ) 2 ω ( ω ! ) 1 ω \frac{(ω)(ω+1)}{2ω}\geq(ω!)^{\frac{1}{ω}} ω + 1 2 ω ( ω ! ) 1 ω ω \frac{ω+1}{2ω}\geq\frac{(ω!)^{\frac{1}{ω}}}{ω}

lim ω 1 + ω 2 ω lim ω ( ω ! ) 1 ω ω \displaystyle\lim_{ω\rightarrow \infty}\frac{1+ω}{2ω}\geq\displaystyle\lim_{ω\rightarrow \infty}\frac{(ω!)^{\frac{1}{ω}}}{ω}

lim ω 1 2 lim ω ( ω ! ) 1 ω ω \displaystyle\lim_{ω\rightarrow \infty}\frac{1}{2}\geq\displaystyle\lim_{ω\rightarrow \infty}\frac{(ω!)^{\frac{1}{ω}}}{ω}

lim ω 1 2 lim ω ( ω ! ) 1 ω ω 0 \displaystyle\lim_{ω\rightarrow \infty}\frac{1}{2}-\displaystyle\lim_{ω\rightarrow \infty}\frac{(ω!)^{\frac{1}{ω}}}{ω}\geq0

This solution is incomplete. First, it does not show that lim ω ( ω ! ) 1 / ω ω \lim_{\omega\to\infty}\frac{(\omega!)^{1/\omega}}{\omega} exists. Also, if the limit does exist , it might be 1 2 \frac{1}{2} . Thus the answer could be "positive", "0", or "can't be determined".

Otto Bretscher - 5 years, 3 months ago

Log in to reply

I have used Stirling formule and I found lim ω ( ω ! ) 1 ω ω = 1 e \large \lim_{\omega\to \infty} \frac{(\omega!)^{\frac{1}{\omega}}}{\omega} = \frac{1}{e}

Guillermo Templado - 5 years, 3 months ago

Log in to reply

Yes that works.... or use a Riemann sum for ln ( x ) \ln(x)

Otto Bretscher - 5 years, 3 months ago

Log in to reply

@Otto Bretscher Great, thank you

Guillermo Templado - 5 years, 3 months ago

Log in to reply

@Guillermo Templado Anytime, Compañero :)

Otto Bretscher - 5 years, 3 months ago

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...