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document.write( "\r\n" );
document.write( "Use the rule
, and repeat it three times to get \r\n" );
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document.write( "
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document.write( "But
so your expression becomes\r\n" );
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document.write( "
\r\n" );
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document.write( "\r\n" );
document.write( "But
for all real a.\r\n" );
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document.write( "So,
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