MA 3972-MA-Book May 8, 2018 13:46
Review of Precalculus 71
Example 1
f(x)=x^3 − 3 x+ 2
The functionf(x)=x^3 − 3 x+2 is increasing on (−∞,−1) and (1,∞) and decreasing on
(−1, 1). A relative minimum value of the function is 0, occurring at the point (1, 0), and a
relative maximum value of 4 is located at the point (−1, 4). (See Figure 5.4-2.)
[−8, 8] by [−5, 5]
Figure 5.4-2
Example 2
g(x)=(x−1)^3
Note thatg(x)=(x−1)^3 is increasing for the entire domain (−∞,∞), and it has no relative
minimum or relative maximum values. (See Figure 5.4-3.)
[−5, 5] by [−4, 4]
Figure 5.4-3
Example 3
f(x)=
x
x− 2
The function f is decreasing on the intervals (−∞, 2) and (2,∞), and it has no relative
minimum or relative maximum values. (See Figure 5.4-4.)
[−5, 5] by [−4, 4]
Figure 5.4-4