That's interesting

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SANZEED
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That's interesting

Unread post by SANZEED » Sun Jul 29, 2012 12:11 am

For positive real numbers $a_{1},a_{2},...,a_{n}$ with $a_{1}a_{2} \cdots a_{n}=1$, prove that $a_{1}^{n-1}+a_{2}^{n-1}+...+a_{n}^{n-1}\geq \frac{1}{a_{1}}+\frac{1}{a_{2}}+...+\frac{1}{a_{n}}$ .
It is from "Inequalities".
Last edited by *Mahi* on Sun Jul 29, 2012 8:43 pm, edited 1 time in total.
Reason: Edited: replaced "integers" with "real numbers"
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SANZEED
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Re: That's interesting

Unread post by SANZEED » Sun Jul 29, 2012 12:16 am

We have to use Tchebyshev's inequality here,and then AM-GM.
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Re: That's interesting

Unread post by sakibtanvir » Sun Jul 29, 2012 3:38 pm

positive integers!!!!!!!!!It would be positive quantities.Edit please.
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Re: That's interesting

Unread post by nafistiham » Sun Jul 29, 2012 5:04 pm

SANZEED wrote: $a_{1}a_{2},...a_{n}=1$
I suppose, that should just have been $a_{1}a_{2}...a_{n}=1$
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SANZEED
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Re: That's interesting

Unread post by SANZEED » Mon Jul 30, 2012 12:14 pm

Thanks to Tiham vai.Yes that was a typo and it's edited.Thanks to Mahi vaia and Sakibtanvir too.
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