Thread: inequality with three vars
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Old September 7th, 2008, 01:24 PM
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4(z-x)^2+4(x-y)^2+(y-z)^2
This is positive

(-2z+z^{4/3}y^{2/3}+y^{4/3}z^{2/3})
This is equal to

(z^{2/3}y^{1/3}-y^{2/3}z^{1/3})^2
That is positive
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