College

If [tex]f(x)=\left(\frac{1}{9}\right)\left(9^x\right)[/tex], what is [tex]f(3)[/tex]?

A. 729
B. [tex]\frac{1}{81}[/tex]
C. [tex]\frac{1}{129}[/tex]
D. 81

Answer :

To solve this problem, we need to find the value of the function [tex]\( f(x) = \left(\frac{1}{9}\right)\left(9^x\right) \)[/tex] when [tex]\( x = 3 \)[/tex].

Let's break it down step-by-step:

1. Substitute [tex]\( x = 3 \)[/tex] into the function:
[tex]\[
f(3) = \left(\frac{1}{9}\right)\left(9^3\right)
\][/tex]

2. Calculate [tex]\( 9^3 \)[/tex]:
[tex]\[
9^3 = 9 \times 9 \times 9 = 729
\][/tex]

3. Multiply [tex]\(\frac{1}{9}\)[/tex] by [tex]\( 729 \)[/tex]:
[tex]\[
\left(\frac{1}{9}\right) \times 729 = \frac{729}{9} = 81
\][/tex]

So, the value of [tex]\( f(3) \)[/tex] is 81.

Therefore, the correct answer is D. 81.