document.write( "Question 1120489: Hey,
\n" ); document.write( "I was hoping that you guys would be able to help me with a problem that I've been stuck on.\r
\n" ); document.write( "\n" ); document.write( "sum^31_(k=3) (1/k - 1/(k+1))\r
\n" ); document.write( "\n" ); document.write( "Sorry, didn't know how to do it in Latex.\r
\n" ); document.write( "\n" ); document.write( "Any help would be greatly appreciated!\r
\n" ); document.write( "\n" ); document.write( "Thanks,
\n" ); document.write( "SaturnV_ \n" ); document.write( "

Algebra.Com's Answer #736151 by ikleyn(52788) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "If I understand your writing correctly, you are asking about the sum\r\n" );
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document.write( "     +  +  + . . . + \r\n" );
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document.write( "Now notice that all intermediate terms cancel each other, since each pair has opposite signs.\r\n" );
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document.write( "The only survived terms are very first and very last,   - .\r\n" );
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document.write( "You may simplify it further, if you want or if you need . . . \r\n" );
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\n" ); document.write( "\n" ); document.write( "Regarding your notice about LATEX, please keep in mind that all postings to this forum must go in the plain text format.\r
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