This table shows values that represent an exponential function.

\begin{tabular}{|c|c|}
\hline
[tex]$x$[/tex] & [tex]$y$[/tex] \\
\hline
0 & 1 \\
\hline
1 & 2 \\
\hline
2 & 4 \\
\hline
3 & 8 \\
\hline
4 & 16 \\
\hline
5 & 32 \\
\hline
6 & 64 \\
\hline
\end{tabular}

What is the average rate of change for this function for the interval from [tex]$x=3$[/tex] to [tex]$x=5$[/tex]?

A. 12

B. 24

C. [tex]$\frac{1}{12}$[/tex]

D. [tex]$\frac{1}{24}$[/tex]



Answer :

To find the average rate of change of a function over a given interval [tex]\([x_1, x_2]\)[/tex], we follow these steps:

1. Identify the interval:
The interval provided is from [tex]\(x = 3\)[/tex] to [tex]\(x = 5\)[/tex].

2. Find the corresponding [tex]\(y\)[/tex]-values for these [tex]\(x\)[/tex]-values from the table:
- When [tex]\(x = 3\)[/tex], [tex]\(y = 8\)[/tex]
- When [tex]\(x = 5\)[/tex], [tex]\(y = 32\)[/tex]

3. Use the formula for the average rate of change:
[tex]\[ \text{Average rate of change} = \frac{y_2 - y_1}{x_2 - x_1} \][/tex]
Here, [tex]\((x_1, y_1) = (3, 8)\)[/tex] and [tex]\((x_2, y_2) = (5, 32)\)[/tex].

4. Substitute the values into the formula:
[tex]\[ \text{Average rate of change} = \frac{32 - 8}{5 - 3} \][/tex]

5. Calculate the differences:
[tex]\[ 32 - 8 = 24 \][/tex]
[tex]\[ 5 - 3 = 2 \][/tex]

6. Divide the differences to find the average rate of change:
[tex]\[ \text{Average rate of change} = \frac{24}{2} = 12 \][/tex]

Thus, the average rate of change for the function over the interval from [tex]\(x = 3\)[/tex] to [tex]\(x = 5\)[/tex] is 12.

So, the correct answer is:
A. 12