volume_mute
Find the Inverse of f(x) = x/(1−x)
publish date: 2026/05/23 21:16:56.675787 UTC
volume_mute
Find \(f^{-1}(x)\) for \(f(x) = \dfrac{x}{1 - x}\).
Correct Answer
\(f^{-1}(x) = \dfrac{x}{1 + x},\; x \ne -1\)
Explanation
Step 1: \(y = \frac{x}{1-x} \Rightarrow y(1-x) = x \Rightarrow y - yx = x \Rightarrow y = x + yx = x(1+y) \Rightarrow x = \frac{y}{1+y}\).
Step 2: \(f^{-1}(y) = \frac{y}{1+y}\,(y \ne -1)\).
Step 3: \(f^{-1}(x) = \frac{x}{1+x}\,(x \ne -1)\).
Reference
Introduction to Differential Calculus (Systematic Studies with Engineering Applications for Beginners) - 2012
