College

Select the correct answer.

Exponential function [tex] f [/tex] is represented by the table.

[tex]
\begin{array}{|c|c|c|c|c|c|}
\hline
x & -2 & -1 & 0 & 1 & 2 \\
\hline
f(x) & -46 & -22 & -10 & -4 & -1 \\
\hline
\end{array}
[/tex]

Function [tex] g [/tex] is represented by the equation:

[tex] g(x) = -18\left(\frac{1}{3}\right)^x + 2 [/tex]

Which statement correctly compares the two functions on the interval [tex] [-1, 2] [/tex]?

A. Both functions are increasing, but function [tex] g [/tex] increases at a faster average rate.

B. Only function [tex] f [/tex] is increasing, but both functions are negative.

C. Both functions are increasing, but function [tex] f [/tex] increases at a faster average rate.

D. Only function [tex] f [/tex] is increasing, and only function [tex] f [/tex] is negative.

Answer :

To determine which statement correctly compares the functions [tex]\( f \)[/tex] and [tex]\( g \)[/tex] on the interval [tex]\([-1, 2]\)[/tex], let's analyze both functions:

### Function [tex]\( f \)[/tex]

Function [tex]\( f \)[/tex] is represented by the following table of values:

[tex]\[
\begin{array}{|c|c|}
\hline
x & f(x) \\
\hline
-2 & -46 \\
-1 & -22 \\
0 & -10 \\
1 & -4 \\
2 & -1 \\
\hline
\end{array}
\][/tex]

Observing the table, notice that as [tex]\( x \)[/tex] increases from [tex]\(-1\)[/tex] to [tex]\(2\)[/tex], the values of [tex]\( f(x) \)[/tex] are [tex]\(-22, -10, -4, -1\)[/tex]. These values are increasing, which means that [tex]\( f(x) \)[/tex] is increasing on this interval.

Also, note that all values of [tex]\( f(x) \)[/tex] are negative for [tex]\( x = -1, 0, 1, \)[/tex] and [tex]\(2\)[/tex].

### Function [tex]\( g \)[/tex]

Function [tex]\( g \)[/tex] is given by the equation:
[tex]\[ g(x) = -18\left(\frac{1}{3}\right)^x + 2 \][/tex]

We calculate [tex]\( g(x) \)[/tex] for [tex]\( x = -1, 0, 1, \)[/tex] and [tex]\(2\)[/tex]:

- [tex]\( g(-1) = -18 \times 3 + 2 = -54 + 2 = -52 \)[/tex]
- [tex]\( g(0) = -18 \times 1 + 2 = -18 + 2 = -16 \)[/tex]
- [tex]\( g(1) = -18 \times \frac{1}{3} + 2 = -6 + 2 = -4 \)[/tex]
- [tex]\( g(2) = -18 \times \frac{1}{9} + 2 = -2 + 2 = 0 \)[/tex]

The values for [tex]\( g(x) \)[/tex] are [tex]\(-52, -16, -4, 0\)[/tex], which consistently increase. Thus, [tex]\( g(x) \)[/tex] is also increasing on this interval.

However, not all values of [tex]\( g(x) \)[/tex] are negative; for example, [tex]\( g(2) = 0 \)[/tex].

### Conclusion

From the analysis:
- Function [tex]\( f \)[/tex] is increasing and negative throughout the interval.
- Function [tex]\( g \)[/tex] is increasing, but not all its values are negative.

Thus, the correct statement is:
A. Both functions are increasing, but function [tex]\( g \)[/tex] increases at a faster average rate.

So, the answer is A.

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