College

If [tex]$f(x)=\left(\frac{1}{7}\right)\left(7^x\right)$[/tex], what is [tex]$f(3)$[/tex]?

A. 343
B. [tex]$\frac{1}{343}$[/tex]
C. [tex]$\frac{1}{49}$[/tex]
D. 49

Answer :

To solve the problem, we need to find the value of the function [tex]\( f(x) = \left(\frac{1}{7}\right)\left(7^x\right) \)[/tex] when [tex]\( x = 3 \)[/tex].

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

1. Substitute [tex]\( x = 3 \)[/tex] into the function [tex]\( f(x) \)[/tex]:
[tex]\[
f(3) = \left(\frac{1}{7}\right)\left(7^3\right)
\][/tex]

2. Calculate [tex]\( 7^3 \)[/tex]:
- [tex]\( 7^3 \)[/tex] means multiplying 7 by itself three times: [tex]\( 7 \times 7 \times 7 = 343 \)[/tex].

3. Multiply [tex]\( \frac{1}{7} \)[/tex] by 343:
- [tex]\[
f(3) = \left(\frac{1}{7}\right) \times 343 = \frac{343}{7}
\][/tex]

4. Calculate [tex]\( \frac{343}{7} \)[/tex]:
- Dividing 343 by 7 gives 49.

So, [tex]\( f(3) = 49 \)[/tex].

Therefore, the correct answer is D. 49.