[" It is known for "x!=1" that "1+x+x^(2)+...+x^(n-1)=(1-x^(n))/(1-x)],[" hence find the sum of the series "S=1+2x+3x^(2)+...],[+(n+1)x^(n)]

it is known for x ne 1 that 1+x+x^(2)+"….."+x^(n-1) = (1-x^(n))/(1-x) , hence find the sum of the series S = 1+2x+3x^(2)+"….."+(n+1)x^(n) .

it is known for x ne 1 that 1+x+x^(2)+"….."+x^(n-1) = (1-x^(n))/(1-x) , hence find the sum of the series S = 1+2x+3x^(2)+"….."+(n+1)x^(n) .

It is known for n ne 1 that : 1+x+x^2+..........+x^(n-1)=(1-x^(n))/(1-x) , hence find the sum of the series: 1+2x+3x^(2)+"….."+(n-1)x^(n-2) .

From the relation 1+x+x^(2)+* * * + x^(n-1)=(1-x^(n))/(1-x) , find the sum of the series 1+2x+3x^(2)+* * * +(n-1)x^(n-2) .

It is known that for x ne 1 , we have 1+x+x^(2)+….+x^(n-1)= (1-x^(n))/(1-x) , using this result, find the sum of the series 1+ 2x + 3x^(2)+…. +(n-1)x^(n-2) .

Sum of n terms of the series 1+2 x+3 x^(2)+4 x^(3)+..,(x ne 1) is

Find the sum of the series 1+2x+3x^2+....(n-1)x^(n-2) using differentiation.

Find the sum of the series 1+2x+3x^(2)+(n-1)x^(n-2) using differentiation.

Find the sum of the series 1+2x+3x^(2)+(n-1)x^(n-2)) using differentiation.