Group commutator
= Group commutator
{title2=$[x,y]=x^{-1}y^{-1}xy$}
{wiki=Commutator}
The group commutator measures the failure of two elements to commute. Under the convention $[x,y]=x^{-1}y^{-1}xy$, it is the identity exactly when $xy=yx$.
= Group commutator
{title2=$[x,y]=x^{-1}y^{-1}xy$}
{wiki=Commutator}
The group commutator measures the failure of two elements to commute. Under the convention $[x,y]=x^{-1}y^{-1}xy$, it is the identity exactly when $xy=yx$.