\b[It is neither <injective> nor <surjective> onto $\mathbb R$, so it has no <inverse function> on the stated domain and codomain.] The distinct inputs $0$ and $\pi/3$ both lie in the domain and both give zero. All values lie in $[-1,1]$, so, for example, the real number $2$ has no preimage.

Solution

Past exam of the year 1 of the computer science course of the University of Oxford / 2019 / Discrete mathematics, continuous mathematics, and probability / 1 / c / ii / Solution

 Solution (source code)