Examples
[032433120]⎡⎢⎣032433120⎤⎥⎦
Step 1
Step 1.1
Consider the corresponding sign chart.
|+-+-+-+-+|∣∣
∣∣+−+−+−+−+∣∣
∣∣
Step 1.2
The cofactor is the minor with the sign changed if the indices match a -− position on the sign chart.
Step 1.3
The minor for a11a11 is the determinant with row 11 and column 11 deleted.
|3320|∣∣∣3320∣∣∣
Step 1.4
Multiply element a11a11 by its cofactor.
0|3320|0∣∣∣3320∣∣∣
Step 1.5
The minor for a12a12 is the determinant with row 11 and column 22 deleted.
|4310|∣∣∣4310∣∣∣
Step 1.6
Multiply element a12a12 by its cofactor.
-3|4310|−3∣∣∣4310∣∣∣
Step 1.7
The minor for a13 is the determinant with row 1 and column 3 deleted.
|4312|
Step 1.8
Multiply element a13 by its cofactor.
2|4312|
Step 1.9
Add the terms together.
0|3320|-3|4310|+2|4312|
0|3320|-3|4310|+2|4312|
Step 2
Multiply 0 by |3320|.
0-3|4310|+2|4312|
Step 3
Step 3.1
The determinant of a 2×2 matrix can be found using the formula |abcd|=ad-cb.
0-3(4⋅0-1⋅3)+2|4312|
Step 3.2
Simplify the determinant.
Step 3.2.1
Simplify each term.
Step 3.2.1.1
Multiply 4 by 0.
0-3(0-1⋅3)+2|4312|
Step 3.2.1.2
Multiply -1 by 3.
0-3(0-3)+2|4312|
0-3(0-3)+2|4312|
Step 3.2.2
Subtract 3 from 0.
0-3⋅-3+2|4312|
0-3⋅-3+2|4312|
0-3⋅-3+2|4312|
Step 4
Step 4.1
The determinant of a 2×2 matrix can be found using the formula |abcd|=ad-cb.
0-3⋅-3+2(4⋅2-1⋅3)
Step 4.2
Simplify the determinant.
Step 4.2.1
Simplify each term.
Step 4.2.1.1
Multiply 4 by 2.
0-3⋅-3+2(8-1⋅3)
Step 4.2.1.2
Multiply -1 by 3.
0-3⋅-3+2(8-3)
0-3⋅-3+2(8-3)
Step 4.2.2
Subtract 3 from 8.
0-3⋅-3+2⋅5
0-3⋅-3+2⋅5
0-3⋅-3+2⋅5
Step 5
Step 5.1
Simplify each term.
Step 5.1.1
Multiply -3 by -3.
0+9+2⋅5
Step 5.1.2
Multiply 2 by 5.
0+9+10
0+9+10
Step 5.2
Add 0 and 9.
9+10
Step 5.3
Add 9 and 10.
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