From the Main Menu, select the MAT icon to enter the Matrix Mode and display the initial screen.

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1 !""#"$$"#% From the Main Menu, select the MAT icon to enter the Matrix Mode and display the initial screen. Creating a Matrix To create a matrix, you must first define its dimensions in the MATRIX list. Then you can input values into the matrix. To specify the dimensions of a matrix with rows and columns named Mat B: a. Highlight Mat B b. Press [] [EXE] to specify the number of rows. c. Press [] [EXE] to specify the number of columns. d. All of the cells of the new Mat B contain the value 0. To input [EXE] [] [EXE]. into Matrix B, press [] [EXE] [] [EXE] [] [EXE] [] [EXE] [] Editing a Matrix To edit a matrix, follow these steps: a. In the MAT Mode, highlight the matrix you want to edit. Press [EXE]. b. Arrow to the cell you want to change. c. Enter the new value and press [EXE]. d. To add a row below another row, highlight the row and press [F] (ROW) [F] (ADD). A new row forms below containing all 0 s.

2 e. You can also use [F] (INS) to insert a row between two existing rows. Viewing a Matrix in the RUN Mode To view a matrix in the RUN Mode, press [OPTN] [F] (Mat) [F] (Mat) [ALPHA] [log] (B) [EXE]. In this example, we use Matrix B. If the matrix is too large to fit on the screen, use the arrow keys to scroll across or down the matrix.!% &'(" You can perform operations with matrices just as with numbers. The following examples use matrices A, B, and C. You can add or subtract matrices if they have the same dimensions. You can multiply two matrices if the number of columns in the first matrix matches the number of rows in the second matrix.

3 You can multiply any matrix by a constant. You can raise a square matrix to a power. The result of a matrix operation can be stored into a matrix or used in the next calculation. This way you can work recursively with matrices by continually pressing [EXE]. Errors If you get a Dim ERROR message, then the dimensions of the matrices do not satisfy the operation s criteria or you have named a matrix that is not defined.!"#)#" You cannot plot a polygon directly from a matrix, but you can convert a matrix into lists of x- and y- coordinates and plot a polygon from the lists. For example, the matrix represents the quadrilateral with vertices (, ), (-, ), (-, -), and (, -). To graph a closed figure, the first point must be repeated as the last point.

4 From the RUN Mode, you can convert the first column of the matrix into List by pressing [OPTN] [F] [F] [F] [ALPHA] [x,θ,t] [,] [] [)] [ ] [OPTN] [F] [F] [] [EXE]. To convert the second column of the matrix into List, press [OPTN] [F] [F] [F] [ALPHA] [x,θ,t] [,] [] [)] [ ] [OPTN] [F] [F] [] [EXE]. So, to plot the polygon represented by a matrix, follow these steps: a. Enter the matrix and store it as matrix [A]. b. Convert the matrix into Lists and as indicated above. c. Set up StatGraph as an xy line graph with List as the Xlist and List as the YList. d. Set an appropriate window and display the graph. *!% &+ '(" The following menu appears whenever you press [F] (R-OP) while a recalled matrix is on the display. Swap row swap Rw scalar product of specified row Rw+ addition of scalar product of specified row to another row Rw+ addition of specified row to another row To swap two rows To swap rows two and three of the following matrix: Press [F] (R-OP) [F] (Swap) [] [EXE] [] [EXE].

5 To calculate the scalar product of a row To calculate the scalar product of row of the following matrix multiplying by : Press [F] (R-OP) [F] ( Rw) [] [EXE] [] [EXE]. To calculate the scalar product of a row and add the result to another row To calculate the scalar product of row of the following matrix multiplying by and add the result to row : Press [F] (R-OP) [F] ( Rw+) [] [EXE] [] [EXE] [] [EXE]. To add two rows together To add row to row of the following matrix:

6 Press [F] (R-OP) [F] (Rw+) [] [EXE] [] [EXE].!$$+,"-. The Casio 970G PLUS/980GB PLUS calculator does not convert an augmented matrix to reduce row-echelon form; however, to solve the system x y + z = 7 x + y z = x + y z = From the Main Menu, highlight the EQUA icon, and press [EXE]. Press [F] to solve a system of simultaneous equations. Press [F] to indicate three unknowns. Enter the coefficients of x, y, z, and constant left to right for each equation. Press [F] to solve the system. -!/"0% To find the inverse of a matrix, enter the name of the matrix and press [SHIFT] [)] (x ). If you get a Dim ERROR message, either the matrix is not square; if you get a Ma ERROR message, one row of the matrix is a multiple of another row. In either case, the matrix has no inverse. 7

7 !(,"#/" Before you can store a graph function in memory, you must first specify its graph type. While the Graph Function Menu is on the display, press [F] (TYPE) to display the graph type menu. Press [F] for the inequality options. Press [F].. [F] depending on the type of inequality you desire. To store the following inequality in memory area Y: y > x x Press [F] (TYPE) [F] [F] (Y>) [x,θ,t] [x ] [-] [x,θ,t] [-] [] [EXE]. Set an appropriate window and press [F] to view its graph. Vertical boundary lines can be approximated with a line of very steep negative slope. An equation in the form y = 000(b x), where b is the x-intercept, works well. These screens show an approximation for x >. Graphing Systems of Inequalities When graphing a system of inequalities, simply enter each inequality as above. Press [F] to view the graph of the system. 8