Britannica AI Icon

Quick Summary

In mathematics, an equivalence relation is a way to generalize the concept of equality between elements of a set. It must satisfy three conditions:1
* Reflexivity: Every element is related to itself.
* Symmetry: If element A is related to element B, then B is also related to A.
* Transitivity: If A is related to B, and B is related to C, then A is related to C.12

An example is the congruence of triangles in geometry. Elements within a set that share an equivalence relation are said to belong to the same equivalence class.1

Two sets are considered equivalent if their members can be paired up exactly, with no members left over on either side. This concept applies to both finite and infinite sets.3

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.