What is the inverse of the function [tex]f(x)=2x+1[/tex]?

A. [tex]h(x)=\frac{1}{2}x-\frac{1}{2}[/tex]
B. [tex]h(x)=\frac{1}{2}x+\frac{1}{2}[/tex]
C. [tex]h(x)=\frac{1}{2}x-2[/tex]
D. [tex]h(x)=\frac{1}{2}x+2[/tex]



Answer :

To determine the inverse of the function [tex]\( f(x) = 2x + 1 \)[/tex], we follow these steps:

1. Express the function as an equation in [tex]\( y \)[/tex] and [tex]\( x \)[/tex]:
[tex]\[ y = 2x + 1 \][/tex]

2. Swap [tex]\( x \)[/tex] and [tex]\( y \)[/tex] to solve for the inverse function:
[tex]\[ x = 2y + 1 \][/tex]

3. Solve this equation for [tex]\( y \)[/tex]:

To isolate [tex]\( y \)[/tex]:
[tex]\[ x - 1 = 2y \][/tex]

Dividing both sides by 2:
[tex]\[ y = \frac{x - 1}{2} \][/tex]

4. Express [tex]\( y \)[/tex] in terms of [tex]\( x \)[/tex]:
[tex]\[ y = \frac{1}{2} x - \frac{1}{2} \][/tex]

Thus, the inverse function [tex]\( f^{-1}(x) \)[/tex] is:
[tex]\[ f^{-1}(x) = \frac{1}{2} x - \frac{1}{2} \][/tex]

Given the choices:
- [tex]\( h(x) = \frac{1}{2} x - \frac{1}{2} \)[/tex]
- [tex]\( h(x) = \frac{1}{2} x + \frac{1}{2} \)[/tex]
- [tex]\( h(x) = \frac{1}{2} x - 2 \)[/tex]
- [tex]\( h(x) = \frac{1}{2} x + 2 \)[/tex]

The correct choice is:
[tex]\[ h(x) = \frac{1}{2} x - \frac{1}{2} \][/tex]