Introduction to Matrices
Matrices are a useful way to represent and manipulate data in order to model situations. The elements in a matrix can represent data, equations or systems and have many real-life applications.
What are matrices?
- A matrix is a rectangular array of elements (numerical or algebraic) that are arranged in rows and columns
- The order of a matrix is defined by the number of rows and columns that it has
- The order of a matrix with rows and columns is
- A matrix can be defined by where and and refers to the element in row , column
What type of matrices are there?
- A column matrix (or column vector) is a matrix with a single column,
- A row matrix is a matrix with a single row,
- A square matrix is one in which the number of rows is equal to the number of columns,
- Two matrices are equal when they are of the same order and their corresponding elements are equal, i.e. for all elements
- A zero matrix, , is a matrix in which all the elements are , e.g.
- The identity matrix, , is a square matrix in which all elements along the leading diagonal are and the rest are , e.g.
What is the transpose of a matrix?
- The transpose of matrix A is denoted as AT
- The transpose matrix is formed by interchanging the rows and columns
Examiner Tip
- Make sure that you know how to enter and store a matrix on your calculator
Worked example
Let the matrix