Matrices

Overview

Description

Matrices are arrays of numbers or organized data. Operations with matrices include addition, subtraction, and multiplication. Matrices may also have inverses. The methods for finding the inverse of a matrix include using a formula, technology, or matrix operations. Matrices can represent systems of linear equations. A variety of techniques can be used to solve systems of equations represented as matrices.

At A Glance

  • Matrices of the same dimensions can be added or subtracted.
  • A scalar product is the product of a real number and a matrix.
  • An m×nm\times n matrix can be multiplied by an n×pn\times p matrix. The result is an m×pm\times p matrix.
  • If a matrix has an inverse, the product of the matrix and its inverse is the identity matrix.
  • There are different methods for determining the inverse of a matrix, including using an augmented matrix and row operations, using technology, and using a formula that includes calculating the reciprocal of the difference of the diagonals.
  • The inverse of a matrix can be used to solve a matrix equation of the form AX=BAX=B.
  • Gaussian elimination is a method of solving systems of linear equations by using an augmented matrix and row operations.
  • Row operations can be used to determine whether a linear system of equations is consistent and independent, inconsistent, or dependent.
  • The determinant of a square matrix is a value related to properties of the matrix.
  • Cramer's rule is a method of using determinants to solve systems of linear equations.