Inverse Function -- from Wolfram MathWorld

Given a function f(x), its inverse f^(-1)(x) is defined by f(f^(-1)(x))=f^(-1)(f(x))=x. (1) Therefore, f(x) and f^(-1)(x) are reflections about the line y=x. In Mathematica, inverse functions are represented using InverseFunction[f]. As noted by Feynman (

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