document.write( "Question 887613: Express the given sums using sigma notation for the following:
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\n" ); document.write( "c) 1/2+1/2×3+1/3×4+...+1/99×100\r
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Algebra.Com's Answer #536745 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "a) 2+5+10+14+18\r\n" );
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document.write( "We can't put that in sigma notation because there is no obvious pattern\r\n" );
document.write( "to those numbers as there is for (b) and (c).  Are you sure you copied (a)\r\n" );
document.write( "right?\r\n" );
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document.write( "I see that the other tutor assumed you meant 6 instead of 5.  Then it's \r\n" );
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document.write( "2+6+10+14+18 = 4-2,8-2,12-2,16-2,20-4.  Each term is 2 less than a multiple\r\n" );
document.write( "of 4 or 4k-2 \r\n" );
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document.write( "b) 5+25+125+625.  That's .  Each term is of the form  where k goes from 1 to 4 \r\n" );
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document.write( "c) 1/2+1/2×3+1/3×4+...+1/99×100\r\n" );
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document.write( "That's .  Each term\r\n" );
document.write( "is of the form  where k goes from 1 to 99.\r\n" );
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document.write( "Edwin

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