## Precalculus (6th Edition)

(a) $(-\infty, -3)$ (b) $(-3, +\infty)$ (c) There is no interval where the function's value is constant.
(a) The graph of the function is falling (decreasing) from the left up to $x=-3$. Thus, the function is decreasing in the interval $(-\infty, -3)$. (b) The graph of the function is rising (increasing) from $x=-3$ to the right. Thus, the function is increasing in the interval $(-3, +\infty)$. (c) There is no part in the graph where the function's value is constant.