\r\n" );
document.write( "The other tutor's proof is wrong. He proved the converse\r\n" );
document.write( "of what you are to prove. He started by assuming\r\n" );
document.write( "the conclusion and proved what was given. You must\r\n" );
document.write( "start with what is given, not with what you are to\r\n" );
document.write( "prove. \r\n" );
document.write( "\r\n" );
document.write( "Here is the correct proof:\r\n" );
document.write( "
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document.write( "If b is a positive number and a < b
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document.write( "show that 


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document.write( "\r\n" );
document.write( "We start with what is given,\r\n" );
document.write( "(not with what we are to prove, as he did):\r\n" );
document.write( "\r\n" );
document.write( "

\r\n" );
document.write( "\r\n" );
document.write( "and use the hint:\r\n" );
document.write( "\r\n" );
document.write( "

\r\n" );
document.write( "\r\n" );
document.write( "We replace 0 by the equivalent ab - ab.\r\n" );
document.write( "\r\n" );
document.write( "

\r\n" );
document.write( "\r\n" );
document.write( "We add ab to both sides:\r\n" );
document.write( " \r\n" );
document.write( "

\r\n" );
document.write( "\r\n" );
document.write( "We add a to both sides\r\n" );
document.write( "\r\n" );
document.write( "

\r\n" );
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document.write( "Factor out common factors on each side\r\n" );
document.write( "\r\n" );
document.write( "

\r\n" );
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document.write( "Divide both sides by b+1, which is positive\r\n" );
document.write( "since b is positive. Therefore we will not \r\n" );
document.write( "reverse the inequality when we divide by b+1:\r\n" );
document.write( "\r\n" );
document.write( "

\r\n" );
document.write( "\r\n" );
document.write( "Divide both sides by b which is positive and\r\n" );
document.write( "also will not reverse the inequality when we \r\n" );
document.write( "divide by it:\r\n" );
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document.write( "

\r\n" );
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document.write( "which is equivalent to\r\n" );
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document.write( "

\r\n" );
document.write( "\r\n" );
document.write( "Edwin
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document.write( "