Sylvester identity for bordered minors

ID: sylvester-identity-for-bordered-minors

Let a square matrix have a leading block . For row and column indices , let be the determinant formed by bordering with row and column , keeping that order. For and , the Sylvester identity for bordered minors is
It is a polynomial identity and remains valid when is singular; dividing by requires an additional nonzero condition.[ref]
For and , the bordered minors are , , . The identity reads . In Bareiss algorithm, this identity explains why division by a previous pivot can be exact over the integers.

New to topics? Read the docs here!