Questions: The one-to-one function f is defined below.
f(x) = 7x / (8x - 1)
Find f^(-1)(x), where f^(-1) is the inverse of f.
Also state the domain and range of f^(-1) in interval notation.
f^(-1)(x) =
Domain of f^(-1)
Range of f^(-1)
Transcript text: The one-to-one function $f$ is defined below.
\[
f(x)=\frac{7 x}{8 x-1}
\]
Find $f^{-1}(x)$, where $f^{-1}$ is the inverse of $f$.
Also state the domain and range of $f^{-1}$ in interval notation.
\[
f^{-1}(x)=
\]
Domain of $f^{-1}$ $\square$
Range of $f^{-1}$ $\square$
Solution
Solution Steps
Step 1: Finding the Inverse Function
To find the inverse of the function \( f(x) = \frac{7x}{8x - 1} \), we set \( y = f(x) \) and solve for \( x \) in terms of \( y \). The resulting inverse function is given by:
\[
f^{-1}(x) = \frac{y}{8y - 7}
\]
Step 2: Determining the Domain of \( f^{-1} \)
The domain of the inverse function \( f^{-1} \) corresponds to the range of the original function \( f(x) \). The range of \( f(x) \) is all real numbers except \( \frac{7}{8} \). Therefore, the domain of \( f^{-1} \) is:
\[
\text{Domain of } f^{-1}: (-\infty, \frac{7}{8}) \cup (\frac{7}{8}, \infty)
\]
Step 3: Determining the Range of \( f^{-1} \)
The range of the inverse function \( f^{-1} \) corresponds to the domain of the original function \( f(x) \). The domain of \( f(x) \) is all real numbers except \( \frac{1}{8} \). Therefore, the range of \( f^{-1} \) is:
\[
\text{Range of } f^{-1}: (-\infty, \frac{1}{8}) \cup (\frac{1}{8}, \infty)
\]