Minors and Cofactors

The matrix created after eliminating the row and column of the matrix in which that specific element lies is defined as the minor of the matrix.

The minor of the element a12 is M12 – [Tex]\left[\begin{matrix}a_{11}&a_{12}&a_{13}\\a_{21}&a_{22}&a_{23}\\a_{31}&a_{32}&a_{33}\\\end{matrix}\right]=\left[\begin{matrix}a_{21}&a_{23}\\a_{31}&a_{33}\\\end{matrix}\right] [/Tex]

The cofactor of an element in matrix A is produced by multiplying the element’s minor  Mij by (-1)i+j . Cij is the symbol for an element’s cofactor. If the minor of a matrix is Mij , then the cofactor of the element would be Cij = (-1)i+j Mij. The cofactor matrix is the matrix created by the cofactors of the matrix’s components.

Cofactor Matrix : [Tex]\left[\begin{matrix}C_{11}&C_{12}&C_{13}\\C_{21}&C_{22}&C_{23}\\C_{31}&C_{32}&C_{33}\\\end{matrix}\right][/Tex]

How to Solve a System of Equations using Inverse of Matrices?

How to Solve a System of Equations Using Inverse of Matrices? In mathematics, a matrix is an array of numbers arranged in a rectangular pattern and separated into rows and columns. They’re commonly depicted by enclosing all of the integers within square brackets.

In this article, we will discuss how to solve a system of equations using the inverse of matrices in detail.

Table of Content

  • Determinant
  • Minors and Cofactors 
  • Adjoint of a matrix 
  • Inverse of a matrix 
  • Application of Matrices and Determinants 
  • Representing linear systems with matrix equations
  • Solving equations with inverse matrices
  • Problems on How to Solve a System of Equations using Inverse of Matrices?
  • Practice Problems on How to Solve a System of Equations using Inverse of Matrices?

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Determinant

A matrix’s determinant is the scalar value produced for a given square matrix. The determinant is dealt with in linear algebra, and it is computed using the elements of a square matrix. A determinant is a scalar value or number calculated using a square matrix. The square matrix might be 2 × 2, 3 × 3, 4 × 4, or any other form where the number of columns and rows are equal, such as n × n. If S is the set of square matrices, R is the set of integers (real or complex), and f: S → R is defined by f (A) = k, where A ∈ S and k ∈ R, then f (A) is referred to as A’s determinant. A determinant is represented by two vertical lines, i.e., |A|....

Minors and Cofactors

The matrix created after eliminating the row and column of the matrix in which that specific element lies is defined as the minor of the matrix....

Adjoint of a matrix

Let A=[aij] be an n-dimensional square matrix. A matrix A’s adjoint is the transpose of A’s cofactor matrix. It is symbolized by the letter adj A. Adjoint matrices are sometimes known as adjugate matrices. The adjoint of a square matrix A = [aij]n x n is defined as the transpose of the matrix [Aij]n x n, where Aij is the cofactor of the element aij....

Inverse of a matrix

A square matrix A is invertible if and only if A is a nonsingular matrix. The inverse of a matrix may be obtained by dividing the adjoint of a matrix by the determinant of the matrix. The inverse of a matrix may be computed by following the steps below:...

Application of Matrices and Determinants

Now, let’s look at how determinants and matrices may be used to solve systems of linear equations in two or three variables and to assess the system’s consistency....

Representing linear systems with matrix equations

An augmented matrix can be used to represent a system of equations. Each row in an augmented matrix represents one of the system’s equations, while each column represents a variable or the constant terms. We can see that augmented matrices are a shortcut for formulating systems of equations in this way....

Solving equations with inverse matrices

Let’s suppose the equation is:   [Tex]a_1x+a_1y+a_3z=d_1 \\b_1x+b_2y+b_3z=d_2\\ c_1x+c_2y+c_3z=d_3[/Tex]...

Problems on How to Solve a System of Equations using Inverse of Matrices?

Question 1: Find the following of the given matrix [Tex]A=\left[\begin{matrix}3&2&-1\\-5&0&-2\\3&4&-1\\\end{matrix}\right][/Tex]...

Practice Problems on How to Solve a System of Equations using Inverse of Matrices?

1. Solve the following system of equations using the inverse of matrices:’...

FAQs on How to Solve a System of Equations using Inverse of Matrices?

How do you find the inverse of a matrix?...