(i)[3]
Determine the exact value of $x$ for which $f(x) = 4$.
(ii)[2]
Give the range of $f$.
(iii)[2]
Sketch the graph of $y = f(x)$.
(iv)[3]
Find a formula for $f^{-1}(x)$.
Mathematics 9709 · AS & A Level · Functions
Functions — practice question
The function $f : x \mapsto 6 - 4\cos\left(\frac{1}{2}x\right)$ is defined over the interval $0 \leq x \leq 2\pi$.