Find the sum of the coefficients in the expansion of `(7+4x)^49`

Find the sum of the coefficients in the expansion of (5x^(6)-(4)/(x^(9)))^(10)

Find the sum of last 20 coefficients in the expansions of (1+x)^(39).

Find the sum of last 20 coefficients in the expansions of (1+x)^(39).

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

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

The sum of the coefficients in the expansion of (1-x)^(10) is

If the sum of the coefficients in the expansion of (x+y)^(n) is 4096, then the greatest coefficient in the expansion is