Answer:
The function f is graphed.
f is an even function as it has U- form.
As per the graph there is one local maximum at (0, 4) and one local minimum at (6, 1).
The global minimum is (-9, -2) and the global maximum is infinity.
The minimum and maximums are the borders of the increasing or decreasing intervals.
<u>Intervals when the function is increasing: </u>
<u>Intervals when the function is decreasing: </u>