Group axioms

These conditions define a group: a set with a binary operation that is closed, associative, has an identity element, and in which every element has an inverse. They are the starting point for all of group theory.

\begin{aligned}&(\cdot)\colon G\times G\to G\\&\forall x,y,z\in G\colon (x\cdot y)\cdot z=x\cdot(y\cdot z)\\&\exists1\in G\forall x\in G\colon 1\cdot x=x\cdot1=x\\&\forall x\in G\exists y\in G\colon x\cdot y=y\cdot x=1\end{aligned}

What the symbols mean

the set forming the group
the binary group operation mapping G\times G to G
arbitrary elements of G
the identity element of G

About this formula

  • FieldMathematics
  • TopicAbstract algebra
  • LevelUniversity
  • Also calledgroup definition, definition of a group, associativity identity inverse, mathematical group, group (algebra), group (math)
  • SourceWikidata Q83478

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