For the function $f(x)=\frac{3 x+2}{x}$, find $f^{-1}(x)$.
The goal is to find the inverse of the function \(f(x) = \frac{3x+2}{x}\). An inverse function \(f^{-1}(x)\) is a function that reverses the effect of \(f(x)\). Specifically, if \(f(a) = b\), then \(f^{-1}(b) = a\). To find the inverse, we follow a systematic algebraic procedure. The function is defined for all \(x eq 0\).
To find the inverse, we start by setting \(y = f(x)\), so we have:
\[y = \frac{3x+2}{x}\]
Next, we swap the roles of \(x\) and \(y\), which gives us the equation for the inverse relation:
\[x = \frac{3y+2}{y}\]
Now, we solve this equation for \(y\) in terms of \(x\).
\[xy = 3y + 2\]
\[xy - 3y = 2\]
\[y(x - 3) = 2\]
\[y = \frac{2}{x - 3}\]
Thus, the inverse function is \(f^{-1}(x) = \frac{2}{x - 3}\).
Inverse functions are essential in various real-life scenarios where we need to reverse an operation. For instance, if a company has a pricing function where the cost \(C\) of producing \(x\) items is \(C(x) = 5x + 100\), the inverse function \(x(C) = \frac{C - 100}{5}\) allows the manager to determine how many items they can produce given a fixed budget \(C\). Similarly, currency conversion rates work as functions, and finding the inverse allows you to quickly convert back to your home currency. Understanding these relationships helps in optimization, budgeting, and data analysis.