What does it mean to find the inverse of a function

In mathematics, an inverse function (or anti-function) is a function that "reverses" another function: if the function f applied to an input x gives a result of y, then applying its inverse function g to y gives the result x, and vice versa, i.e., f(x) = y if and only if g(y) = x. Courtesy to Wikipedia

the 2 figures are congruent bc if you reflect abcd over the y axis then over the d axis the figures overlap

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