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#1 2011-07-18 00:32:14

Thanh Vān
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Nice Inequality

Let a,b,c,d be positive real numbes. prove that

 

#2 2011-07-18 02:16:24

gAr
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Re: Nice Inequality

Hi Thanh Vān,

Welcome to the forum!

Last edited by gAr (2011-07-18 02:19:09)


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."
 

#3 2011-07-18 10:28:37

Thanh Vān
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Re: Nice Inequality

Oh. Hi gAr. I don't understand your proof.
Why you have

 

#4 2011-07-18 13:07:26

gAr
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Re: Nice Inequality

Hi,



I thought since 8 is the minimum value LHS can have, we may write like that.


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."
 

#5 2011-07-18 21:00:15

bobbym
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Re: Nice Inequality

Hi;

For anyone else wishing to work on the problem here it is latexed.


In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.
 

#6 2011-07-20 00:39:08

Thanh Vān
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Re: Nice Inequality

I thinks idea of gAr is wrong and can't use it to prove inequality. It can solve by Cauchy Schwarz Inequality and AM-GM Inequality very beautiful.

 

#7 2011-07-20 20:10:34

gAr
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Re: Nice Inequality

Hi Thanh Vān,

Yes, I was wrong. I made wrong assumption without checking.
Anyway, I could prove



and



But unable to get anywhere.

Last edited by gAr (2011-07-22 15:02:17)


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."
 

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