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## #1 Re: Exercises » Function » 2011-07-23 17:15:30

Can you completed your proof for my problem?Thanks.

## #2 Re: Exercises » Function » 2011-07-22 02:51:01

I thinks you idea is not true. We must find f(x) from its condition.

Oh. I have find

## #4 Re: Exercises » Inequality In [1;3] » 2011-07-21 23:14:20

Hi gAr, I don't see you completed solution for my inequality (=left your proven). Please see again your post. Thanks.

## #5 Exercises » Function » 2011-07-20 15:43:17

Thanh Vân
Replies: 8

Find the function

such that

## #6 Re: Exercises » Nice Inequality » 2011-07-19 02:39:08

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 Re: Exercises » Inequality In [1;3] » 2011-07-19 02:30:31

Hi anonimnystefy.
Look my inequality, you can see Maximun of left Inequality is when a=b=c=3 and minimum right inequality is same as yourself.
But it is very easy to talk so.
I thinks it is a problem very very nice, and we can solve it by basic 's inequality.
Maybe it is CS and AM-GM.

## #8 Exercises » Inequality In [1;3] » 2011-07-17 12:33:52

Thanh Vân
Replies: 5

Let a,b,c be real numbers in [1;3]. prove that

## #9 Re: Exercises » Nice Inequality » 2011-07-17 12:28:37

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

## #10 Exercises » Nice Inequality » 2011-07-17 02:32:14

Thanh Vân
Replies: 6

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