Given that x=259\displaystyle x = \frac{25}{9}x=925, find the value of x−12\displaystyle x^{\frac{-1}{2}}x2−1, giving your answer as a fraction in its lowest terms.
233 exam-style questions on Edexcel A Level Maths Algebraic Expressions, covering 1.1 Index Laws, 1.2 Expanding Brackets, 1.3 Factorising, 1.4 Negative and Fractional Indices, and 1.5 Surds. Each one has a worked solution and a mark scheme showing where the marks go.