Work out the first three terms in the binomial expansion of (1+3x)12\displaystyle (1 + 3x)^{\frac{1}{2}}(1+3x)21.
Write down the range of values of x x\,x for which the expansion is valid.
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.