Knowledge Base

Solution 10351: Finding the Inverse of a Matrix on the TI-85 or TI-86 Graphing Calculator.

How do I find the inverse of a matrix with the TI-85 or TI-86 graphing calculator?

The example below will demonstrate how to find the inverse of a matrix on the TI-85 or TI-86 graphing calculator.

Example: Find the inverse of matrix A

A = [1 2
        3 4]

Solution:

1) Press [2nd] [7](MATRX) [F2] to enter the matrix editor.
2) Input [A] press [ENTER]
3) Input the dimensions of the matrix (2 [ENTER] 2 [ENTER])
4) Input the values for the elements of the matrix pressing [ENTER] after each entry
5) Press [Exit] to return to the home screen

To find the inverse of matrix A:

1) Press [2nd] [7](MATRX) [F1] [F1] the screen should show A
2) Press [2nd] [EE](X-1) [ENTER]

The displayed answer will show:

[[ -2 1 ] [ 1.5 -5]]