Mathematics 9709 · AS & A Level · Functions

Functions — practice question

The functions $f$ and $g$ are given by $f(x) = x^2 - 4x + 3$ for $x > c$, where $c$ is a constant, and $g(x) = \frac{1}{x+1}$ for $x > -1$.
(a)[2]

Express $f(x)$ so that it is written as $(x-a)^2 + b$.

(b)[1]

State the minimum value of $c$.

(c)[3]

Find an expression for $f^{-1}(x)$ and state the domain for $f^{-1}$.

(d)[3]

Find an expression for $gf(x)$ and state the range of values of $gf$.

Worked solution & mark scheme

This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: Complete the square to obtain $(x-2)^2-1$

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI