(i(a))[2]
When $k = 2$, determine the range of $f$.
(i(b))[3]
When $k = 2$, find the exact solutions of the equation $f(x) = 1$.
(ii(a))[2]
For $k = 1$, sketch the graph of $y = f(x)$.
(ii(b))[1]
State whether $f$ has an inverse, and give a reason.
Mathematics 9709 · AS & A Level · Functions
Functions — practice question
The function $f$ is specified by $f(x) = 3 - 4\cos^k x$, for $0 \leq x \leq \pi$, and $k$ is a constant.