document.write( "Question 461590: if a and b are two distinct non-negative numbers, prove that a^4+b^4>ab(a^2+b^2) \n" ); document.write( "
Algebra.Com's Answer #316524 by robertb(5830)\"\" \"About 
You can put this solution on YOUR website!
Not both of a and b are equal to zero, by the given. Assume one of them, say a, is zero, but \"b+%3C%3E+0\". Then \"b%5E4+%3E+0%2Ab%2A%280%2Bb%29+=+0\", which is always true.
\n" ); document.write( "Hence assume that both a and b are positive.\r
\n" ); document.write( "\n" ); document.write( "Then \r
\n" ); document.write( "\n" ); document.write( "\"%28a-b%29%5E2%28a%5E2+%2B+ab+%2B+b%5E2%29+%3E+0\"
\n" ); document.write( "<==> \"%28a-b%29%28a-b%29%28a%5E2+%2B+ab+%2B+b%5E2%29+%3E+0\"
\n" ); document.write( "<==> \"%28a%5E3-b%5E3%29%28a+-+b%29+%3E+0\"
\n" ); document.write( "<==> \"a%5E3%28a-b%29+-+b%5E3%28a-b%29+%3E+0\"
\n" ); document.write( "<==> \"a%5E3%28a-b%29+%2B+b%5E3%28b-a%29+%3E+0+\"\r
\n" ); document.write( "\n" ); document.write( "<==> \"a%5E4+-+a%5E3b+%2B+b%5E4+-+ab%5E3+%3E+0\"\r
\n" ); document.write( "\n" ); document.write( "<==> \"a%5E4+%2B+b%5E4+%3E+a%5E3b+%2B+ab%5E3\"\r
\n" ); document.write( "\n" ); document.write( "<==> \"a%5E4+%2B+b%5E4+%3E+ab%28a%5E2+%2B+b%5E2%29\"
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