Question

determine all intervals on which the graph of f is decreasing.

Explanation:

Step1: Identify decreasing - slope sections

A function $y = f(x)$ is decreasing when the slope of the graph is negative.

Step2: Observe the graph

Looking at the graph, we see that the function is decreasing on the intervals where the curve goes down as we move from left - to - right.

Step3: Determine the intervals

From the graph, the function $f(x)$ is decreasing on the intervals $(-2,0)$, $(3,5)$ and $(6,\infty)$.

Answer:

$(-2,0),(3,5),(6,\infty)$