What is the inverse function of [tex]$f(x)=\frac{x}{x-2}$[/tex]?

[tex]
\begin{array}{l}
A. \ f^{-1}(x)=-\frac{2 x}{x-1} \\
B. \ f^{-1}(x)=\frac{x-2}{x} \\
C. \ f^{-1}(x)=\frac{2 x}{x-1} \\
D. \ f^{-1}(x)=\frac{2 x}{x+1}
\end{array}
[/tex]



Answer :

To find the inverse function of [tex]\( f(x) = \frac{x}{x-2} \)[/tex], we need to follow a detailed step-by-step process to solve for [tex]\( x \)[/tex] in terms of [tex]\( y \)[/tex] and then express [tex]\( x \)[/tex] as a function of [tex]\( y \)[/tex].

1. Start with the given function:
[tex]\[ f(x) = \frac{x}{x-2} \][/tex]

2. Replace [tex]\( f(x) \)[/tex] with [tex]\( y \)[/tex] to signify the output of the function:
[tex]\[ y = \frac{x}{x-2} \][/tex]

3. Solve for [tex]\( x \)[/tex] in terms of [tex]\( y \)[/tex]. Begin by eliminating the fraction by cross-multiplying:
[tex]\[ y(x-2) = x \][/tex]

4. Distribute [tex]\( y \)[/tex] on the left-hand side:
[tex]\[ yx - 2y = x \][/tex]

5. Isolate the [tex]\( x \)[/tex] terms by getting all [tex]\( x \)[/tex] terms on one side of the equation:
[tex]\[ yx - x = 2y \][/tex]

6. Factor out [tex]\( x \)[/tex] from the left-hand side:
[tex]\[ x(y - 1) = 2y \][/tex]

7. Solve for [tex]\( x \)[/tex] by dividing both sides by [tex]\( y - 1 \)[/tex]:
[tex]\[ x = \frac{2y}{y - 1} \][/tex]

8. To find the inverse function [tex]\( f^{-1}(x) \)[/tex], replace [tex]\( y \)[/tex] with [tex]\( x \)[/tex] in the expression:
[tex]\[ f^{-1}(x) = \frac{2x}{x - 1} \][/tex]

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