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Topic: proof of an inequality
Replies: 12   Last Post: Apr 24, 2013 9:02 AM

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 oercim@yahoo.com Posts: 237 Registered: 5/2/05
Re: proof of an inequality
Posted: Apr 23, 2013 11:28 AM
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Okey, I guess I got it. Let n=2,

x1^2+x2^2>=((x1+x2)^2)/4

==>4(x1^2+x2^2)>=(x1+x2)^2
==>3(x1^2+x2^2)>=2x1x2

if x1=x2 (not 0) it is obvious it holds,

if x1 is not equal x2, then one is greater then another one. Let sat x1>x2

Then x1^2>x1x2. I guess it is easy to apply n variable case. Thanks alot.

Date Subject Author
4/23/13 oercim@yahoo.com
4/23/13 Paul
4/23/13 oercim@yahoo.com
4/23/13 Paul
4/23/13 oercim@yahoo.com
4/23/13 oercim@yahoo.com
4/23/13 Paul
4/23/13 Ken.Pledger@vuw.ac.nz
4/23/13 Virgil
4/24/13 Paul
4/24/13 Leon Aigret
4/24/13 Paul
4/24/13 Paul

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