User Manual

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The following describes only the matrix commands that are used for matrix arithmetic
operations.
• { Mat } ... {Mat command (matrix specification)}
• { Det } ... {Det command (determinant command)}
• { Trn } ... {Trn command (transpose matrix command)}
• { Iden } ... {Identity command (identity matrix input)}
• { Ref } ... {Ref command (row echelon form command)}
• { Rref } ... {Rref command (reduced row echelon form command)}
All of the following examples assume that matrix data is already stored in memory.
u Matrix Arithmetic Operations [OPTN] - [MAT] - [Mat]/[Iden]
Example 1 To add the following two matrices (Matrix A + Matrix B):
AK2(MAT) 1(Mat) av(A) +
1(Mat) al(B) w
Example 2 To multiply the two matrices in Example 1 (Matrix A × Matrix B)
AK2(MAT) 1(Mat) av(A) *
1(Mat) al(B) w
• The two matrices must have the same dimensions in order to be added or subtracted. An
error occurs if you try to add or subtract matrices of different dimensions.
• For multiplication (Matrix 1 × Matrix 2), the number of columns in Matrix 1 must match the
number of rows in Matrix 2. Otherwise, an error occurs.
u Determinant [OPTN] - [MAT] - [Det]
Example Obtain the determinant for the following matrix:
Matrix A =
1 2 3
4 5 6
−1 −2 0
K2(MAT) 3(Det) 1(Mat)
av(A) w
• Determinants can be obtained only for square matrices (same number of rows and columns).
Trying to obtain a determinant for a matrix that is not square produces an error.
• The determinant of a 2 × 2 matrix is calculated as shown below.
| A | =
a
11
a
12
=a
11
a
22
–a
12
a
21
a
21
a
22
A =
1
1
2 1
2 3
2 1
B =
A =
1
1
2 1
2 3
2 1
B =