Inverse functions undo each other. If f(a) = b, then f⁻¹(b) = a. The graphs reflect across y = x. Functions as a set are in ACT Math functions.
Swap x and y
To find an inverse algebraically, replace f(x) with y, swap x and y, solve for y. Composition f(f⁻¹(x)) should return x, in function composition. Notation f(x) itself is in function notation.
Evaluating f at a point in Desmos is in evaluating a function at a point.
The bottom line
Inverse undoes. Swap coordinates, or swap x and y and solve.
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