document.write( "Question 827159: Prove than sum(1/(r^2),r=1,n)is greater than or equal to 2- (1/n) for n is greater than or equal to 1. \r
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Algebra.Com's Answer #498816 by Edwin McCravy(20059)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "\"cross%28%28sum%281%2Fr%5E2%2Cr=1%2Cn%29%29%3E=2-1%2Fn%29\"\r\n" );
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document.write( "This is not true!\r\n" );
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document.write( "Although equality holds for n=1:\r\n" );
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document.write( "\"1%2F1%5E2\"\"%22%22=%22%22\"\"1\"\r\n" );
document.write( "\"2-1%2F1\"\"%22%22=%22%22\"\"1\"\r\n" );
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document.write( "It isn't true for n=2 or greater, for when n=2\r\n" );
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document.write( "\"1%2F1%5E2%2B1%2F2%5E2\"\"%22%22=%22%22\"\"1%2B1%2F4\"\"%22%22=%22%22\"\"1.25\"\r\n" );
document.write( "yet\r\n" );
document.write( "\"2-1%2F2\"\"%22%22=%22%22\"\"1.5\", \"%22%22%3C=%22%22\" holds but not \"%22%22%3E=%22%22\"\r\n" );
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document.write( "And when n=3\r\n" );
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document.write( "\"1%2F1%5E2%2B1%2F2%5E2%2B1%2F2%5E3\"\"%22%22=%22%22\"\"1%2B1%2F4%2B1%2F8\"\"%22%22=%22%22\"\"1.375\"\r\n" );
document.write( "yet\r\n" );
document.write( "\"2-1%2F3\"\"%22%22=%22%22\"\"1.666667\", again \"%22%22%3C=%22%22\" holds but not \"%22%22%3E=%22%22\".\r\n" );
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document.write( "Euler proved in 1735 that the the sum on the left approaches the irrational\r\n" );
document.write( "number \"pi%5E2%2F6\" = 1.6449340668482264... and it is an increasing function, so it\r\n" );
document.write( "is always less that \"pi%5E2%2F6\".\r\n" );
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document.write( "The expression on the right is also increasing, and approaches 2.  But\r\n" );
document.write( "beginning with the third term it is already larger than the left side can \r\n" );
document.write( "ever be!\r\n" );
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document.write( "Edwin
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