document.write( "Question 711123: If a, b, c are positive real numbers prove that
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document.write( "(a + b + c)(1/a + 1/b + 1/c) >= 9\r
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document.write( "I'm lost as to how to begin this proof \n" );
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Algebra.Com's Answer #437332 by KMST(5328)![]() ![]() You can put this solution on YOUR website! First you multiply and simplify. \n" ); document.write( "I would also rearrange as shown below. \n" ); document.write( " \n" ); document.write( "Next we have to show that each expression in brackets is equal or greater than 2. \n" ); document.write( "All of them are of the form \n" ); document.write( " \n" ); document.write( "We could probe it with \n" ); document.write( " \n" ); document.write( "We want to prove that \n" ); document.write( " \n" ); document.write( "so \n" ); document.write( "And since x and y are positive xy is a positive number we can use to divide both sides of the inequality to find that \n" ); document.write( " \n" ); document.write( "Then \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "So \n" ); document.write( " \n" ); document.write( " |