Definition:Equivalence Relation/Definition 1
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Definition
Let $\RR$ be a relation on a set $S$.
Let $\RR$ be:
- $(1): \quad$ reflexive
- $(2): \quad$ symmetric
- $(3): \quad$ transitive
Then $\RR$ is an equivalence relation on $S$.
Also known as
An equivalence relation is frequently referred to just as an equivalence.
Also denoted as
When discussing equivalence relations, various notations are used for $\tuple {x, y} \in \RR$.
Examples are:
- $x \mathrel \RR y$
- $x \equiv \map y \RR$
- $x \equiv y \pmod \RR$
and so on.
Specialised equivalence relations generally have their own symbols, which can be defined as they are needed.
Such symbols include:
- $\cong$, $\equiv$, $\sim$, $\simeq$, $\approx$
Also see
- Results about equivalence relations can be found here.
Sources
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