The average rate of change is 1 on the interval [tex]-3 \leq x \leq 0[/tex]. The average rate of change is 5 on the interval [tex]0 \leq x \leq 3[/tex]. What is the average rate of change of [tex]g[/tex] on the interval [tex]3 \leq x \leq 6[/tex]?



Answer :

Let's find the average rate of change of the function [tex]\( g(x) \)[/tex] on the interval [tex]\( 3 \leq x \leq 6 \)[/tex].

### Step-by-Step Solution:

1. Understanding given intervals and rates:
- The average rate of change on the interval [tex]\(-3 \leq x \leq 0\)[/tex] is 1.
- The average rate of change on the interval [tex]\(0 \leq x \leq 3\)[/tex] is 5.

2. Determine function values at key points:
Let's assume [tex]\( g(-3) = 0 \)[/tex] to simplify our calculations.

- Interval [tex]\(-3\)[/tex] to [tex]\(0\)[/tex]:
[tex]\[ g(0) = g(-3) + \text{rate of change} \times (\text{length of the interval}) \][/tex]
Substituting the values:
[tex]\[ g(0) = 0 + 1 \times (0 - (-3)) \][/tex]
[tex]\[ g(0) = 0 + 1 \times 3 = 3 \][/tex]

- Interval [tex]\(0\)[/tex] to [tex]\(3\)[/tex]:
[tex]\[ g(3) = g(0) + \text{rate of change} \times (\text{length of the interval}) \][/tex]
Substituting the values:
[tex]\[ g(3) = 3 + 5 \times (3 - 0) \][/tex]
[tex]\[ g(3) = 3 + 5 \times 3 = 3 + 15 = 18 \][/tex]

3. Calculate function value at [tex]\(x = 6\)[/tex]:
To find [tex]\(g(6)\)[/tex] on the interval [tex]\(3 \leq x \leq 6\)[/tex], we assume the rate of change remains constant at 5 (as given).

- Interval [tex]\(3\)[/tex] to [tex]\(6\)[/tex]:
[tex]\[ g(6) = g(3) + \text{rate of change} \times (\text{length of the interval}) \][/tex]
Substituting the values:
[tex]\[ g(6) = 18 + 5 \times (6 - 3) \][/tex]
[tex]\[ g(6) = 18 + 5 \times 3 = 18 + 15 = 33 \][/tex]

4. Calculate the average rate of change on the interval [tex]\(3 \leq x \leq 6\)[/tex]:
The average rate of change between [tex]\(x = 3\)[/tex] and [tex]\(x = 6\)[/tex] is:
[tex]\[ \text{Average rate of change} = \frac{g(6) - g(3)}{6 - 3} \][/tex]
Substituting the values:
[tex]\[ \text{Average rate of change} = \frac{33 - 18}{6 - 3} \][/tex]
[tex]\[ \text{Average rate of change} = \frac{15}{3} = 5 \][/tex]

Therefore, the average rate of change of [tex]\(g\)[/tex] on the interval [tex]\(3 \leq x \leq 6\)[/tex] is [tex]\( \boxed{5} \)[/tex].