Texas Instruments TI-92 Getting Started page 27

Figure 5.74: Data/Matrix menu
The display will show the matrix by showing a grid with zeros in the rows and columns specified in the definition of
the matrix.
Use the cursor pad or press ENTER repeatedly to move the cursor to a matrix element you want to change. If you
press ENTER, you will move right across a row and then back to the first column of the next row. The lower left of
the screen shows the cursor's current location within the matrix. The element in the second row and first column in
Figure 5.75 is highlighted, so the lower left of the window is r2c1 = –1. showing that element's current value. Enter
all the elements of matrix a; pressing ENTER after inputting each value.
When you are finished, leave the editing screen by pressing 2nd QUIT or
5.6.2 Matrix Math: From the Home screen, you can perform many calculations with matrices. To see matrix a,
press A ENTER (Figure 5.76).
Perform the scalar multiplication 2 a pressing 2A ENTER. The resulting matrix is displayed on the screen. To
create matrix b as 2a press 2 A STO➧ B ENTER (Figure 5.77), or if you do this immediately after calculating 2a,
press only STO➧ B ENTER. The calculator will display the matrix.
Figure 5.76: Matrix a
To add two matrices, say a and b, create b (with the same dimensions as a) and then press A + B ENTER. Again, if
you want to store the answer as a specific matrix, say m, then press STO➧ M. Subtraction is performed in similar
manner.
Now create a matrix called c with dimensions of 2×3 and enter the matrix
multiplication of c by a, press C × A ENTER. If you tried to multiply a by c, your TI-92 would notify you of an
error because the dimensions of the two matrices do not permit multiplication in this way.
The transpose of a matrix is another matrix with the rows and columns interchanged. The symbol for the transpose
T T
of a is a . To calculate a , press A 2nd MATH 4[Matrix] 1[
2 7
Graphing Technology Guide: TI-92
Copyright © Houghton Mifflin Company. All rights reserved.
Figure 5.75: Editing a matrix
HOME to return to the Home screen.
Figure 5.77: Matrix b

2 0 3

− −
1 5 1

T
] ENTER.

as c. For matrix

