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

1. Express the function in terms of [tex]\( y \)[/tex]:
[tex]\[ y = 2x + 1 \][/tex]

2. Swap [tex]\( y \)[/tex] and [tex]\( x \)[/tex]:
[tex]\[ x = 2y + 1 \][/tex]

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

4. Rewrite the inverse function:
[tex]\[ f^{-1}(x) = \frac{x - 1}{2} \][/tex]

5. Compare the form of the inverse function with the options provided:

- [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]

6. The correct form of the inverse function [tex]\(\frac{x - 1}{2}\)[/tex] can be rewritten as:
[tex]\[ \frac{x - 1}{2} = \frac{1}{2} x - \frac{1}{2} \][/tex]

Therefore, the inverse function is:

[tex]\[ h(x) = \frac{1}{2} x - \frac{1}{2} \][/tex]

From the given options, this corresponds to the first function.

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