Find the sum of the coefficients in the expansion of `(1+2x+3x^2+ n x^n)^2dot`

The sum of the coefficient in the expansion of (1 + x+x^2)^n is

The sum of the coefficient in the expansion of (1 + x+x^2)^n is

Find the sum of the coefficients in the expansion of (1+2x+3x^(2)+...nx^(n))^(2)

Suppose the sum of the coefficients in the expansion of (1 - 5x + 12x^(3))^(n) is a and the sum of the coefficients in the expansion of (1 - 2x + 3x^(2))^n is b. If a = b^(m) , then m = ___

The sum of the coefficient in the expansion of (1+ax-2x^(2))^(n) is

The sum of the coefficient in the expansion of (1+ax-2x^(2))^(n) is

The sum of the coefficient in the expansion of (1+ax-2x^(2))^(n) is

If the sum of the coefficients in the expansion of (1 -3x + 10x^2)^(n) is a and the sum of the coefficients in the expansion of (1 - x^(2))^(n) is b , then

If the sum of the coefficients in the expansion of (1-3x+10x^2)^n is a and if the sum of the coefficients in the expansion of (1+x^2)^n is b, then