Find the binomial expansion of (125+75x)13\displaystyle (125 + 75x)^{\frac{1}{3}}(125+75x)31 in ascending powers of xxx, up to and including the term in x3x^3x3.
Find the range of values of x x\,x for which this expansion is valid.
67 exam-style questions on WJEC A Level Maths 3.4.1 Sequences and Series (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.