# Cartesian product

From Conservapedia

The **Cartesian product** of two sets *A* and *B* is the set (usually denoted by *A × B*) consisting of all ordered pairs *(a, b)* where and . The Cartesian product is named after René Descartes, who invented this concept.

A common example of a Cartesian product is the coordinate plane, . This is all ordered pairs *(a,b)* of real numbers *a* and *b*. It is used for graphing functions on the real numbers.