document.write( "Question 1133418: Σn=1 2/(n(n+1))
\n" ); document.write( "ITS AN INFINITE SERIES AND STARTS AT 1. \n" ); document.write( "

Algebra.Com's Answer #750636 by ikleyn(52790) $\"\"$ $\"About$

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document.write( "The requested sum is  (it is how I read the problem)\r\n" );
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document.write( " +  +  + . . .  + . . . to infinity = \r\n" );
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document.write( "        Each term   =  - .\r\n" );
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document.write( "        Therefore, any finite sum    +  +  + . . .  = \r\n" );
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document.write( "        = ( - ) + ( - ) + ( - ) + . . . + ( - ) = all interior terms cancel each other, \r\n" );
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document.write( "           and only two extreme (very first and very last) terms survive\r\n" );
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document.write( "         = 2 - .\r\n" );
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document.write( "It implies that the limit of the sum  at  n -->oo  is  2 (two, TWO).   ANSWER.\r\n" );
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