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## #1 Re: Help Me ! » inequality » 2005-11-01 21:19:52

the teacher were given me ( can you post the solution )

## #2 Help Me ! » inequality » 2005-11-01 16:22:55

math
Replies: 2

a,b,c>0 . Prove the inequality :
1/[a.\sqrt{a+b}] + 1/[b.\sqrt{b+c}]+1/[c.\sqrt{c+a}]    >=  3/(\sqrt{2abc}

## #3 Re: Help Me ! » geometry » 2005-10-30 20:48:52

the problem were unsolve in along time ago !!!!!!!!!

## #4 Help Me ! » need help » 2005-10-30 10:36:14

math
Replies: 0

triangle ABC (AB<AC )  , AD is a bisector prove with all I, J on AD we have
angleJBI >angleJCI

## #6 Re: Help Me ! » geometry » 2005-10-26 10:41:27

next week , i will give the proof to my teacher ,please , !!!!!!!

## #7 Re: Help Me ! » geometry » 2005-10-24 23:40:33

very thanks to ganesh !!!!

nobody

## #10 Re: Help Me ! » geometry » 2005-10-19 23:56:06

thanks . I will be waiting for you

## #12 Re: Help Me ! » geometry » 2005-10-18 00:52:14

MathsIsFun wrote:

Where did they come from? I had a quick look and found I couldn't give an immediate answer

i don't understand . Why !!!!!!!!!!!!!!
are you have the answer of the problem ????

## #13 Re: Help Me ! » geometry » 2005-10-17 22:29:43

please i'm  very very need !!!!!!!

## #14 Re: Help Me ! » geometry » 2005-10-17 15:35:54

can you post the answer ?

## #15 Re: Help Me ! » geometry » 2005-10-17 11:12:07

nobody can help me !!!!!!!!

## #16 Help Me ! » geometry » 2005-10-17 02:12:44

math
Replies: 21

A)
I is a point in triangle ABC such that angle IBA > angle ICA , angle IBC > angle ICB , BI cut AC at B' , CI cut AB at C' . PRove the : BB' < CC'

and the second problem
B)

a,b,c>0 prove the equation have 1 root :
d^3 - d(ab+bc+ca) - 2abc =0 .

from the equation and x,y,z >0 . ax+by+cz=xyz . Prove the inequality

x+y+z >= 2/d . (\sqrt[(a+d)(b+d)(c+d)])

C)in assemble N ,every number is white or black so that white + black=black
prove : white + white = white