document.write( "Question 144803:
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Algebra.Com's Answer #105747 by Edwin McCravy(20055)\"\" \"About 
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25. solve for n if \"P%28n%2C3%29=2C%28n%2C2%29\", n € N
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document.write( "\"P%28N%2CR%29+=+N%2A%28N-1%29%2A%28n-2%29\"··· (until there are R factors)\r\n" );
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document.write( "So\r\n" );
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document.write( "\"P%28n%2C3%29=n%28n-1%29%28n-2%29\"\r\n" );
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document.write( "and\r\n" );
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document.write( "\"C%28n%2C2%29=n%28n-1%29%2F%282%2A1%29\"\r\n" );
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document.write( "So\r\n" );
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document.write( "\"P%28n%2C3%29=2C%28n%2C2%29\" \r\n" );
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document.write( "becomes:\r\n" );
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document.write( "\"n%28n-1%29%28n-2%29=2%28n%28n-1%29%2F2%29\"\r\n" );
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document.write( "\"n%28n-1%29%28n-2%29=cross%282%29%28n%28n-1%29%2Fcross%282%29%29\"\r\n" );
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document.write( "\"n%28n-1%29%28n-2%29=n%28n-1%29\"\r\n" );
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document.write( "\"n%28n-1%29%28n-2%29-n%28n-1%29=0\"\r\n" );
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document.write( "Factor out \"n%28n-1%29\" on left side:\r\n" );
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document.write( "\"n%28n-1%29%28%28n-2%29-1%29=0\"\r\n" );
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document.write( "\"n%28n-1%29%28n-2-1%29=0\"\r\n" );
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document.write( "\"n%28n-1%29%28n-3%29=0\"\r\n" );
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document.write( "Set each factor = 0\r\n" );
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document.write( "\"n=0\"\r\n" );
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document.write( "\"n-1=0\" or \"n=1\"\r\n" );
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document.write( "\"n-3=0\" or \"n=3\"\r\n" );
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document.write( "So there are three solutions, \"n=0\", \"n=1\", \"n=3\"\r\n" );
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document.write( "Edwin
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