Determinant. Casio FX-9750G

Matrix Calculations k Determinant

The following is the format for obtaining a determinant.

3 (Det)

Matrix

Mat A

Mat Z

MatAns w

6 - 4

Example Obtain the determinant for the following matrix :

1 2 3

Matrix A = 4 5 6

–1 –2 0

3 (Det) 1 (Mat) a A w

1 2 3 4 5 6

This display indicates determinant |A| = –9.

• 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 (Dim 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

• The determinant of a 3

×

3 matrix is calculated as shown below.

a

11 a

12 a

13

| A | = a

21 a

22 a

23 a

31 a

32 a

33

= a

11 a

22 a

33

+ a

12 a

23 a

31

+ a

13 a

21 a

32

– a

11 a

23 a

32

– a

12 a

21 a

33

– a

13 a

22 a

31

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