document.write( "Question 1054496: Evaluate:\r
\n" ); document.write( "\n" ); document.write( "4
\n" ); document.write( "(sigma sign here) 1/2 r(r+1)
\n" ); document.write( "r=1 \n" ); document.write( "

Algebra.Com's Answer #669746 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!

\n" ); document.write( " $\"S=+%281%2F2%29%281%2A2%2B2%2A3%2B3%2A4%2B4%2A5%29\"$
\n" ); document.write( " $\"S=+%281%2F2%29%282%2B6%2B12%2B20%29\"$
\n" ); document.write( " $\"S=1%2B3%2B6%2B10\"$
\n" ); document.write( " $\"S=20\"$ \n" ); document.write( "

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