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document.write( "1. If
, show that the solution set of the inequality
consists of all numbers x for which
.\r\n" );
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document.write( "Let us assume for contradiction that there exists x such that\r\n" );
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document.write( "
, yet
\r\n" );
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document.write( "Since
, x is negative for it is less than a negative number.\r\n" );
document.write( "Then -x is a positive number and \r\n" );
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document.write( "
[both sides are positive]. Therefore,\r\n" );
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which contradicts
.\r\n" );
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document.write( "That's half the proof.\r\n" );
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document.write( "Now assume for contradiction that there exists x such that\r\n" );
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document.write( "
such that
, yet
\r\n" );
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document.write( "Since
,
which contradicts
\r\n" );
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document.write( "Thus the proof is done, and \r\n" );
document.write( " \r\n" );
document.write( "
,
implies
.\r\n" );
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document.write( "------------------\r\n" );
document.write( "2. If
, show that the solution set of the inequality
\r\n" );
document.write( "consists of all numbers x for which
or
.\r\n" );
document.write( "\r\n" );
document.write( "Assume for contradiction that there exists x such that\r\n" );
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document.write( "
and
, yet
\r\n" );
document.write( "\r\n" );
document.write( "Then both
and x are negative numbers, and thus -x is a \r\n" );
document.write( "positive number.\r\n" );
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document.write( "
implies
thus
\r\n" );
document.write( "\r\n" );
document.write( "which contradicts
\r\n" );
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document.write( "That's half the proof. \r\n" );
document.write( "\r\n" );
document.write( "Next, assume for contradiction that there exists x such that\r\n" );
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document.write( "
and
, yet
\r\n" );
document.write( "\r\n" );
document.write( "Then
implies
which contradicts
.\r\n" );
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document.write( "Then
,
implies
\r\n" );
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document.write( "Edwin
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