(a)[2]
Express $f(x)$ as $2(x + a)^2 + b$.
(b)[1]
Find the range for $f$.
(c)[3]
Find a formula for $f^{-1}(x)$.
(d)[2]
The function $g$ is given by $g(x) = 2x + 4$ for $x < -1$. Find and simplify an expression for $fg(x)$.
Mathematics 9709 · AS & A Level · Functions
Functions — practice question
The function $f$ is given by $f(x) = 2x^2 - 16x + 23$ for $x < 3$.
Worked solution & mark scheme
This 8-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Identify the squared term $2(x-4)^2$ and the constant term $-9$.” …
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