find

Asked by  | 3rd Oct, 2008, 07:38: PM

Expert Answer:

tn  =  [ 1+2+3+.. + n]/n  =  n (n+1) /2n  = (n+1)/2

Sn   = tn  = [ n+1]/ 2   =  1/2[ n(n+1) / 2  +  n]  =  1/2 [n(n+1)/2 ]  =  n(n+1 )  /  4

Answered by  | 11th Oct, 2008, 09:50: PM

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