document.write( "Question 924485: Prove algebraically that
\n" ); document.write( "(2n+1)^2-(2n+1) is an even number\r
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Algebra.Com's Answer #728796 by ikleyn(52780) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "    For any integer n the number    is even.\r\n" );
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document.write( "    Indeed,   = n*(n-1)  is the product of two consecutive integers.\r\n" );
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document.write( "    Of the two, one integer inevitably is even.\r\n" );
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document.write( "    Therefore, the product,  n*(n-1)  is even.\r\n" );
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document.write( "    Hence, the original    is even.\r\n" );
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