Texas Instruments TITANIUM TI-89 - Manual (Page 747)

Activities 747
Exploring a 3x3 Matrix Exploring a 3x3 Matrix Exploring a 3x3 Matrix Exploring a 3x3 Matrix
Perform these steps to generate a random matrix, augment and find the identity matrix,
and then solve to find an invalid value of the inverse.
1. On the Home screen, use RandSeed to
set the random number generator seed to
the factory default, and then use
randMat( ) to create a random 3x3 matrix
and store it in a .
2. Replace the [2,3] element of the matrix
with the variable x , and then use the
augment( ) function, to augment the 3x3
identity to a and store the result in b .
3. Use rref( ) to “row reduce” matrix b :
The result will have the identity matrix in
the first three columns and
a^ L 1 in the last
three columns.
Note: Use the cursor in the history area to
scroll the result.