Binary function

In mathematics, a binary function also called bivariate function, or function of two variables, is a function that takes two inputs.

Precisely stated, a function ${\displaystyle f}$ is binary if there exists sets ${\displaystyle X,Y,Z}$ such that

where ${\displaystyle X\times Y}$ is the Cartesian product of ${\displaystyle X}$ and ${\displaystyle Y.}$

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