lt_(x rarr1)(x+x^(2)+x^(3)+......+x^(n)-n)/(x-1)=

lim_(x rarr1)((x+x^(2)+x^(3)++x^(n))-n)/(x-1)

Evaluate lim_(x rarr 1) ((x + x^2 + .........+ x^n)-n)/(x - 1)

If lim_(x rarr 1)((x+x^2+x^3+....+x^n-n)/(x-1))=820 , then find n.

If lim_(x rarr 1)((x+x^2+x^3+....+x^n-n)/(x-1))=820 , then find n.

The value of lim_(x rarr1)(x^(n)+x^(n-1)+x^(n-2)+...x^(2)+x-n)/(x-1)

underset(x to 1)"Lt" (x+x^(2)+...+x^(n)-n)/(x-1)=

lim_(x rarr1)((1-x)(1-x^(2))...(1-x^(2n)))/({(1-x)(1-x^(2))...(1-x^(n))}^(2)),n in N, equals ^2nP_(n)(b)^(2n)C_(n)(c)(2n)!(d) none of these

lim_(x rarr1)((1-x)(1-x^(2))............(1-x^(2n)))/({(1-x)(1-x^(2)).........(1-x^(n))}^(2))