Find the first three terms, in ascending powers of xxx, in the expansion of (3+kx)4(3 + kx)^4(3+kx)4 where k k\,k is a positive constant.
Hence, given that the coefficient of x x\,x is four times the coefficient of x2x^2x2, find the value of kkk.
144 exam-style questions on AQA A Level Maths 1.7.1 Binomial expansion. Each one has a worked solution and a mark scheme showing where the marks go.