Show that 117+7\displaystyle \frac{1}{\frac{1}{\sqrt{7}} + \sqrt{7}}71+71 can be written in the form 7k\displaystyle \frac{\sqrt{7}}{k}k7 where k k\,k is an integer to be found.
217 exam-style questions on CCEA GCSE Maths Surds. Each one has a worked solution and a mark scheme showing where the marks go.