Casio fx-FD10 Pro User Manual page 76

u Reduced Row Echelon Form
This command finds the reduced row echelon form of a matrix.
Example To find the reduced row echelon form of the following matrix:
Matrix A =
K2(MAT)6(g)5(Rref)
6(g)1(Mat)a1(A-E)1(A)w
• The row echelon form and reduced row echelon form operation may not produce accurate
results due to dropped digits.
u Matrix Inversion
Example To invert the following matrix:
Matrix A =
K2(MAT)1(Mat)
a1(A-E)1(A)!a(CATALOG)
a6(SYBL)4( )c~c(–1)ww
• Only square matrices (same number of rows and columns) can be inverted. Trying to invert a
matrix that is not square produces an error.
• A matrix with a determinant of zero cannot be inverted. Trying to invert a matrix with
determinant of zero produces an error.
• Calculation precision is affected for matrices whose determinant is near zero.
• A matrix being inverted must satisfy the conditions shown below.
–1 –1
A A = A A = E =
The following shows the formula used to invert Matrix A into inverse matrix A
a b
A =
c d
1
–1
A =
ad – bc
Note that ad – bc ≠ 0.
2 2 −1 −1 3 3
1 1 1 1 −5 −5
0 0 4 4 3 3
1 1 2 2
3 3 4 4
1 0
0 1
d –b
–c a
3-46
19 19
−21 −21
0 0
[OPTN]-[MAT] -[Rref]
x
–1
[ ]
–1
.