The function f f\,f is defined by
f(x)=4x−5x−2,x∈R, x≠2 f(x)=\frac{4x-5}{x-2},\quad x\in\mathbb{R},\ x\neq2 f(x)=x−24x−5,x∈R, x=2Find f−1(5)f^{-1}(5)f−1(5), and show that ff(x)=ax+b2x−1ff(x) = \dfrac{ax+b}{2x-1}ff(x)=2x−1ax+b where a a\,a and b b\,b are integers to be found.
471 exam-style questions on Edexcel A Level Maths Functions and Graphs, covering 2.1 The Modulus Function, 2.2 Functions and Mappings, 2.3 Composite Functions, 2.4 Inverse Functions, 2.5 y=|f(x)| and y=f(|x|), 2.6 Combining Transformations, and 2.7 Solving Modulus Problems. Each one has a worked solution and a mark scheme showing where the marks go.