Identity matrix

From Citizendium
Revision as of 03:15, 9 December 2008 by imported>Paul Wormer
Jump to navigation Jump to search
This article is a stub and thus not approved.
Main Article
Discussion
Related Articles  [?]
Bibliography  [?]
External Links  [?]
Citable Version  [?]
 
This editable Main Article is under development and subject to a disclaimer.

In matrix algebra, the identity matrix is a square matrix which has all the entries on the main diagonal equal to one and all the other, off-diagonal, entries equal to zero. The identity matrix acts as the identity element for matrix multiplication. Its entries are those of the Kronecker delta.

The identity matrix is also known as unit matrix because it possesses many of the properties of the multiplicative unit of an algebraic field.