Texas Instruments Titanium TI-89 User Manual

Activities 747
Exploring a 3x3 Matrix
Exploring a 3x3 MatrixExploring 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^L1 in the last
three columns.
Note: Use the cursor in the history area to
scroll the result.

Texas Instruments Titanium TI-89 Specifications

General

Display Type	LCD
Display Resolution	160 x 100 pixels
Memory	188 KB RAM, 2.7 MB Flash ROM
Type	Graphing Calculator
Display	Monochrome
Processor	Motorola 68000
Processor Speed	12 MHz
Power Source	4 AAA batteries
Connectivity	USB
Programming	TI-BASIC, Assembly
Operating System	AMS (Advanced Mathematics Software)