In Wikipedia it says that "A $n\times n$ matrix of a ring $R$ is commutative if and only if $n=1$ and $R$ is commutative". Could someone please provide me with a proof/reference to a proof of that ?
Criterion for commutativity of matrices
1
$\begingroup$
matrices
-
1Hint: All you need is to find two $2\times 2$ matrices that do not commute. – 2012-12-08
-
1http://groupprops.subwiki.org/wiki/Center_of_general_linear_group_is_group_of_scalar_matrices_over_center – 2012-12-08
-
1I cannot find your exact quote there. How is a single matrix commutative? – 2012-12-08