Question

Use the binomial theorem

The coefficient of x^4 in the expansion of (3x+4)^6

Answer 1

(a+b)^n = nC0*(a)^(n-0)*(b)^0 + nC1*(a)^(n-1)*(b)^1 + nC2*(a)^(n-2)*(b)^2 + ... + nCn*(a)^(n-n)*(b)^n
to get the coefficient of x^4, just verify 6C2*(3x)^(6-2)*(4)^2