Differentiation - Increasing and Decreasing Functions

A function \(f\) is defined for \(-4 \leq x \leq 3\). The graph of \(f\) is given below.

The graph has a local maximum when \(x = 0\), and local minima when \(x = -3 , x = 2\).

1. Write down the \(x\)-intercepts of the graph of the \(\textbf{derivative}\) function \(f\).[2]
2. Write down all values of \(x\) for which \(f'(x)\) is positive.[2]
3. At point D on the graph of \(f\), the \(x\)-coordinate is \(-0.5\). Explain why \(f'(x) < 0\) at D.[2]