The functions fff and ggg are defined by
f(x)=3+4lnx,x>0 f(x) = 3 + 4\ln x, \quad x > 0 f(x)=3+4lnx,x>0 g(x)=8x−42x+1,x>12 g(x) = \frac{8x - 4}{2x + 1}, \quad x > \frac{1}{2} g(x)=2x+18x−4,x>21Find f−1(15)f^{-1}(15)f−1(15).
Use differentiation to prove that ggg is an increasing function.
Find g−1(x)g^{-1}(x)g−1(x).
Find the range of the composite function fgfgfg.
Practise Edexcel A Level Maths Functions and Graphs with exam-style questions for A Level Maths. 121 questions 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, matched to the Edexcel A Level Maths (9MA0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
