Mathematics 9709 · AS & A Level · Functions

Functions — practice question

The function $f$ is given by $f(x) = x^2 - 4x + 7$ when $x > 2$.
(i)[3]

Express $f(x)$ in the form $(x-a)^2 + b$ and so determine the range of $f$.

(ii)[3]

Obtain an expression for $f^{-1}(x)$ and give the domain of $f^{-1}$.

(iii)[1]

The function $g$ is given by $g(x) = x - 2$ for $x > 2$. The function $h$ satisfies $f = hg$ and has domain $x > 0$. Obtain an expression for $h(x)$.

Worked solution & mark scheme

This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: Writes the quadratic as $(x-2)^2$

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