Chapter 1 - Section 1.3 - More on Functions and Their Graphs - Concept and Vocabulary Check - Page 194: 1

$ \lt f(x_2)$ $\gt f(x_2)$ $= f(x_2)$

Recalling the definitions of increasing, decreasing and constant functions, we have: - $f$ is increasing on $I$ if $f(x_1)\lt f(x_2)$ when $x_1\lt x_2$ - $f$ is decreasing on $I$ if $f(x_1)\gt f(x_2)$ when $x_1\lt x_2$ - $f$ is constant on $I$ if $f(x_1)= f(x_2)$.