Math Interactive
2. Functions
2.2. Inverse functions
2.2.0. Introduction

An inverse function is a function that “reverses” the original.

For example, if f(2)=3,f(2)=3, then a reverse function will take 33 as the input and return 2.2. Denoting this function as f−1,f^{-1}, we have f−1(3)=2.f^{-1}(3)=2.

3{3}
2{2}
f{f}
3{3}
2{2}
f−1{f^{-1}}

However, such a procedure may not lead to a well-defined function, so in the next section we will discuss when such inverse functions exist.

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