inequalities

magic

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Joined
Oct 4, 2011
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9
Is this the correct way?

\(\displaystyle AC^2 D+2ABCD+A^2 BC>BCD^2+B^2 D^2+AB^2 D+A^2 C^2\)

\(\displaystyle (AC-BD)(AB-AC+BD+CD)>0\)

greater that 0 when \(\displaystyle (AC-BD)>0\ \ and\ \ (AB-AC+BD+CD)>0\)

and when \(\displaystyle (AC-BD)<0\ \ and\ \ (AB-AC+BD+CD)<0\)


\(\displaystyle so\ \ AC^2 D+2ABCD+A^2 BC>BCD^2+B^2 D^2+AB^2 D+A^2 C^2\)

\(\displaystyle when\ \ AC>BD\ \ and\ \ AB+CD>AC-BD\)

\(\displaystyle or\ \ AC<BD\ \ and\ \ AB+CD<AC-BD\)

Is there anything else I should be doing with this or a 'correct' way of presenting it?

Thanks
 
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