### Home > CALC > Chapter 8 > Lesson 8.2.1 > Problem8-72

8-72.

Multiple Choice: The function $f$, whose graph consists of two line segments, is shown at right. Which of the following are true for $f$ on the open interval $\left(a, c\right)$?

1. The domain of the derivative of $f$ is the open interval $\left(a, c\right)$.

Is there anywhere within $a < x < c$ in which the derivative does not exist?

2. f is continuous on the open interval $\left(a, c\right)$.

Check all three conditions of continuity.

3. The derivative of $f$ is positive on the open interval $(b, c)$.

A positive derivative means that $f(x)$ is increasing.

1. I only

1. II only

1. III only

1. II & III only

1. I, II & III