document.write( "Question 888258: Sum the Series:
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document.write( "1×2+2×3+3×4+4×5+⋯+2013×2014
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Algebra.Com's Answer #537264 by rothauserc(4718)![]() ![]() You can put this solution on YOUR website! This is a quadratic series whose members are given as \n" ); document.write( " 2 6 12 20 30 ......4054182 \n" ); document.write( " 1 2 3 4 5 2013 \n" ); document.write( "n^2 1 4 9 16 25 4052169 \n" ); document.write( "a member in the geometric sequence is given by \n" ); document.write( "nth term = n^2 +n \n" ); document.write( "now we know that the summation of n^2 = n[n+1][2n+1]/6 and \n" ); document.write( "summation of n is n(n+1)/2 \n" ); document.write( "therefore the sum(S) of the series is \n" ); document.write( "S = 2013(2014)(2*2013+1)/6 + 2013(2014)/2 \n" ); document.write( "S = 16326190914/6 + 4054182/2 \n" ); document.write( "S = 2721031819 + 2027091 \n" ); document.write( "S = 2723058910 \n" ); document.write( " \n" ); document.write( " |