Expand (16−3x)12\displaystyle (16 - 3x)^{\frac{1}{2}}(16−3x)21 in ascending powers of x x\,x up to and including the term in x3x^3x3.
Write down the range of values of x x\,x for which the expansion is valid.
Use your expansion, with a suitable value of xxx, to find the value of 15.7 \sqrt{15.7}\,15.7 correct to 5 significant figures.
231 exam-style questions on WJEC A Level Maths 3.4 Sequences and Series (A-level only), covering 3.4.1 Sequences and Series (A-level only), 3.4.2 Sequences and Series (A-level only), 3.4.3 Sequences and Series (A-level only), 3.4.4 Sequences and Series (A-level only), 3.4.5 Sequences and Series (A-level only), 3.4.6 Sequences and Series (A-level only), and 3.4.7 Sequences and Series (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.