Determinants

In this section, we will learn to write the expansion of a determinant in compact form using minors and cofactors.

Definition 1 Minor of an element \(a_{ij}\) of a determinant is the determinant obtained by deleting its ith row and jth column in which element \(a_{ij}\) lies. Minor of an element \(a_{ij}\) is denoted by \(M_{ij}\)

Remark Minor of an element of a determinant of order \(n(n\ge2)\) is a determinant of order \(n-1\).