A matrix is a rectangular array of numbers arranged in rows and columns. Matrix operations are mathematical operations that can be performed on matrices, such as addition, subtraction, multiplication, inversion, and more. Matrices are useful for representing and solving systems of linear equations, transformations, vectors, and more.

Finding matrix operations on a ti-89 calculator is easy and can be done in two ways: using the MATH menu or using the Data/Matrix Editor application. In this article, we will explain both methods with examples.
Using the MATH menu
The MATH menu is a built-in menu on the ti-89 calculator that can perform various matrix operations, such as creating, editing, transposing, inverting, and multiplying matrices. For example, suppose we want to create a 2×3 matrix A and multiply it by a 3×2 matrix B.
To perform matrix operations using the MATH menu, follow these steps:
- Press the
ONbutton to turn on the calculator. - Press the
MODEbutton and make sure thatEXACTis selected for the exact/approximate mode. - Press the
HOMEbutton to go to the home screen. - Press the
2NDbutton and then press theMATHbutton to access the math menu. - Scroll over to the
Matrixoption (#4) and pressENTERto select it. - Scroll down until you see the
newMat(function and pressENTERto select it. - Enter the row and column dimensions of the matrix separated by commas. For our example, we would enter
2,3for matrix A. - Press the
)button to close the parentheses and press theSTO>button to store the matrix to a variable. For our example, we would pressSTO>A. - Press the
ENTERbutton to create the matrix A. The calculator will display the matrix as[0 0 0][0 0 0]. - Press the
2NDbutton and then press theMATHbutton to access the math menu again. - Scroll over to the
Matrixoption (#4) and pressENTERto select it. - Scroll down until you see the
newMat(function and pressENTERto select it. - Enter the row and column dimensions of the matrix separated by commas. For our example, we would enter
3,2for matrix B. - Press the
)button to close the parentheses and press theSTO>button to store the matrix to a variable. For our example, we would pressSTO>B. - Press the
ENTERbutton to create the matrix B. The calculator will display the matrix as[0 0][0 0][0 0]. - To edit the matrix elements, press the
2NDbutton and then press theVAR-LINKbutton to access the variable manager. - Scroll down until you see the matrix variable that you want to edit and press
ENTERto select it. For our example, we would selectA. - Press the
ENTERbutton again to edit the matrix A. The calculator will display the matrix in the data editor. - Use the arrow keys to move to the element that you want to change and enter the new value. For our example, we would enter the following values for matrix A:
| A |
|---|
| 1 2 3 |
| 4 5 6 |
- Press the
HOMEbutton to go back to the home screen. - Repeat the same steps to edit the matrix B. For our example, we would enter the following values for matrix B:
| B |
|---|
| 7 8 |
| 9 10 |
| 11 12 |
- To perform matrix operations, press the
2NDbutton and then press theMATHbutton to access the math menu again. - Scroll over to the
Matrixoption (#4) and pressENTERto select it. - Scroll down until you see the operation that you want to perform and press
ENTERto select it. For our example, we would select*for matrix multiplication. - Enter the names of the matrices that you want to operate on separated by commas. For our example, we would enter
A,B. - Press the
)button to close the parentheses and pressENTERto calculate the result.

The calculator will display the result as [58 64][139 154]. This means that the product of matrix A and matrix B is this matrix.
Using the Data/Matrix Editor application
The Data/Matrix Editor application is a custom application that can be downloaded and installed on the ti-89 calculator. It can perform various matrix operations, such as creating, editing, transposing, inverting, and multiplying matrices. For example, suppose we want to create a 3×3 matrix C and invert it.
To perform matrix operations using the Data/Matrix Editor application, follow these steps:
- Download the application from this website1 and transfer it to your calculator using the TI Connect software.
- Press the
ONbutton to turn on the calculator. - Press the
APPSbutton and scroll down to the optionData/Matrix Editorand pressENTERto select it. - Press the
ENTERbutton again to run the application. - Press the
F1button and then press the1button to create a new matrix. - Enter the name of the matrix and press
ENTER. For our example, we would enterC. - Enter the row and column dimensions of the matrix separated by commas. For our example, we would enter
3,3for matrix C. - Press the
ENTERbutton to create the matrix C. The calculator will display the matrix as[0 0 0][0 0 0][0 0 0]. - To edit the matrix elements, use the arrow keys to move to the element that you want to change and enter the new value. For our example, we would enter the following values for matrix C:
| C |
|---|
| 1 2 3 |
| 4 5 6 |
| 7 8 9 |
- To perform matrix operations, press the
F2button and then press the1button to access the matrix operations menu. - Scroll down until you see the operation that you want to perform and press
ENTERto select it. For our example, we would selectinv(for matrix inversion. - Enter the name of the matrix that you want to operate on. For our example, we would enter
C. - Press the
)button to close the parentheses and pressENTERto calculate the result.
The calculator will display the result as [-3/2 3/2 -1/2][1 -2 1][1/2 -1/2 0]. This means that the inverse of matrix C is this matrix.
Summury
In this article, we learned how to find matrix operations on a ti-89 calculator using two methods: using the MATH menu and using the Data/Matrix Editor application. Matrix operations are useful for working with systems of linear equations, transformations, vectors, and more. We hope this article was helpful and informative. For more information on matrix operations and other math concepts, you can check out this website.