If the value of limx→1 x+x2+…+xn−nx−1 , is

We have,limz→1 x+x2+x3+…+xn−nx−1=limx→1 (x−1)+x2−12+x3−13+…..+xn−1nx−1=limx→1 x−1x−1+x2−12x−1+x3−13x−1+…+xn−1nx−1=1+2(1)2−1+3(1)3−1+…..+n(1)n−1=1+2+3+……+n=n(n+1)2