Select the correct answer.

What is the inverse of the function [tex]f(x) = \frac{3 - x}{7}[/tex]?

A. [tex]f^{-1}(x) = 3 - 7x[/tex]

B. [tex]f^{-1}(x) = 3 - \frac{x}{7}[/tex]

C. [tex]f^{-1}(x) = 7x - 3[/tex]

D. [tex]f^{-1}(x) = \frac{7 + x}{3}[/tex]



Answer :

To determine the inverse of the function [tex]\( f(x) = \frac{3 - x}{7} \)[/tex], we need to follow a series of steps:

1. Replace [tex]\( f(x) \)[/tex] with [tex]\( y \)[/tex]:
[tex]\[ y = \frac{3 - x}{7} \][/tex]

2. Interchange [tex]\( x \)[/tex] and [tex]\( y \)[/tex]. This step helps us find the inverse function:
[tex]\[ x = \frac{3 - y}{7} \][/tex]

3. Solve for [tex]\( y \)[/tex] in terms of [tex]\( x \)[/tex]:

- First, clear the fraction by multiplying both sides by 7:
[tex]\[ 7x = 3 - y \][/tex]

- Next, isolate [tex]\( y \)[/tex] by subtracting 3 from both sides:
[tex]\[ 7x - 3 = -y \][/tex]

- Finally, multiply both sides by -1 to solve for [tex]\( y \)[/tex]:
[tex]\[ y = 3 - 7x \][/tex]

4. Replace [tex]\( y \)[/tex] with [tex]\( f^{-1}(x) \)[/tex] to express the inverse function:
[tex]\[ f^{-1}(x) = 3 - 7x \][/tex]

After performing all the steps, we determine that the inverse of the function [tex]\( f(x) = \frac{3 - x}{7} \)[/tex] is:

[tex]\[ f^{-1}(x) = 3 - 7x \][/tex]

The correct answer is:

A. [tex]\( f^{-1}(x) = 3 - 7x \)[/tex]