Maths > Matrices and Determinants > 4.0 Determinant of a square matrix
Matrices and Determinants
1.0 Introduction
2.0 Algebra of Matrices
3.0 Special Matrices
3.1 (a) Symmetric Matrix:
3.2 (b) Skew Symmetric Matrix:
3.3 (c) Hermitian matrix:
3.4 (d) Skew Hermitian Matrix:
3.5 (e) Singular and Non-singular Matrices:
3.6 (f) Orthogonal Matrix :
3.7 (g) Idempotent Matrix :
3.8 (h) Unitary Matrix :
3.9 (i) Involuntary Matrix:
3.10 (j) Nilpotent Matrix:
4.0 Determinant of a square matrix
5.0 Adjoint of a square Matrix
6.0 Inverse of a Matrix
7.0 Types of Equations Homogenous & Non-Homogenous
8.0 Cramer's rule
9.0 Types of Linear Equations
4.1 Minors & Cofactors
3.2 (b) Skew Symmetric Matrix:
3.3 (c) Hermitian matrix:
3.4 (d) Skew Hermitian Matrix:
3.5 (e) Singular and Non-singular Matrices:
3.6 (f) Orthogonal Matrix :
3.7 (g) Idempotent Matrix :
3.8 (h) Unitary Matrix :
3.9 (i) Involuntary Matrix:
3.10 (j) Nilpotent Matrix:
Let $\Delta $ be a deteminant. Then minor of element ${a_{ij}}$,denoted by ${M_{ij}}$,is defined as the determinant of the submatrix obtained by ${i^{th}}$ row & ${i^{th}}$ column of $\Delta $ . cofactor of element ${a_{ij}}$ denoted by ${C_{ij}}$ , is defined as ${C_{ij}}$ =${\left( { - 1} \right)^{i + j}}$ ${\left( { - 1} \right)^{i + j}}$ ${M_{ij}}$.
Example:
$\Delta $ = $\left| {\begin{array}{c} a&b \\ c&d \end{array}} \right|$
Then ${M_{11}} = {\text{ }}d{\text{ }} = C11$
${M_{12}} = c,{C_{12}} = - c$
${M_{21}} = b,{C_{21}} = - b$
${M_{22}} = a{\text{ }} = {C_{22}}$