(x+y)*(x+z)*(y+z)>=8xyz

How to show this, I suppose somehow with the AM–GM inequality, but don't know how.

Thank you!

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- December 18th 2011, 09:40 AMgotmejerryInequality
(x+y)*(x+z)*(y+z)>=8xyz

How to show this, I suppose somehow with the AM–GM inequality, but don't know how.

Thank you!

- December 18th 2011, 10:20 AMprincepsRe: Inequality
- December 18th 2011, 10:23 AMgotmejerryRe: Inequality
Thank you!

- December 18th 2011, 10:24 AMprincepsRe: Inequality
you are welcome

- December 18th 2011, 10:29 AMILikeSerenaRe: Inequality
Just nitpicking...

For x=1, y=-1, z=-1, you get:

which is a contradiction. :rolleyes: - December 18th 2011, 10:32 AMPlatoRe: Inequality
- December 18th 2011, 11:03 AMgotmejerryRe: Inequality
Sorry, I forgot that x,y,z are postives:D