1. inverse mappingMathematics
Wikipedia definition
2. Inverse functionIn mathematics, an inverse function is a function that undoes another function: If an input x into the function ƒ produces an output y, then putting y into the inverse function g produces the output x, and vice versa. i.e. , ƒ(x)=y, and g(y)=x. More directly, g(ƒ)=x, meaning g(x) composed with ƒ(x) leaves x unchanged.
Read “Inverse function” on English Wikipedia
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Read “Inverse function” on DBpedia


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