Let $f(x)= \begin{cases}x^2+4 x, & -3 \leq x \leq 0 \\ -\sin x, & 0<x \leq \pi / 2 . \\ -\cos x-1, & \pi / 2<x \leq \pi\end{cases}$ Then, which one of the following is not true?
Answer & explanation
Correct answer: option 4
It is evident from the graph of the function that options (a), (b) and (c) are true.
