Ejemplos
[011142334]⎡⎢⎣011142334⎤⎥⎦
Paso 1
Paso 1.1
Choose the row or column with the most 00 elements. If there are no 00 elements choose any row or column. Multiply every element in row 11 by its cofactor and add.
Paso 1.1.1
Consider the corresponding sign chart.
|+-+-+-+-+|∣∣
∣∣+−+−+−+−+∣∣
∣∣
Paso 1.1.2
The cofactor is the minor with the sign changed if the indices match a -− position on the sign chart.
Paso 1.1.3
The minor for a11a11 is the determinant with row 11 and column 11 deleted.
|4234|∣∣∣4234∣∣∣
Paso 1.1.4
Multiply element a11a11 by its cofactor.
0|4234|0∣∣∣4234∣∣∣
Paso 1.1.5
The minor for a12a12 is the determinant with row 11 and column 22 deleted.
|1234|∣∣∣1234∣∣∣
Paso 1.1.6
Multiply element a12a12 by its cofactor.
-1|1234|−1∣∣∣1234∣∣∣
Paso 1.1.7
The minor for a13a13 is the determinant with row 11 and column 33 deleted.
|1433|∣∣∣1433∣∣∣
Paso 1.1.8
Multiply element a13a13 by its cofactor.
1|1433|1∣∣∣1433∣∣∣
Paso 1.1.9
Add the terms together.
0|4234|-1|1234|+1|1433|0∣∣∣4234∣∣∣−1∣∣∣1234∣∣∣+1∣∣∣1433∣∣∣
0|4234|-1|1234|+1|1433|0∣∣∣4234∣∣∣−1∣∣∣1234∣∣∣+1∣∣∣1433∣∣∣
Paso 1.2
Multiplica 00 por |4234|∣∣∣4234∣∣∣.
0-1|1234|+1|1433|0−1∣∣∣1234∣∣∣+1∣∣∣1433∣∣∣
Paso 1.3
Evalúa |1234|∣∣∣1234∣∣∣.
Paso 1.3.1
El determinante de una matriz 2×22×2 puede obtenerse usando la fórmula |abcd|=ad-cb∣∣∣abcd∣∣∣=ad−cb.
0-1(1⋅4-3⋅2)+1|1433|0−1(1⋅4−3⋅2)+1∣∣∣1433∣∣∣
Paso 1.3.2
Simplifica el determinante.
Paso 1.3.2.1
Simplifica cada término.
Paso 1.3.2.1.1
Multiplica 44 por 11.
0-1(4-3⋅2)+1|1433|0−1(4−3⋅2)+1∣∣∣1433∣∣∣
Paso 1.3.2.1.2
Multiplica -3−3 por 22.
0-1(4-6)+1|1433|0−1(4−6)+1∣∣∣1433∣∣∣
0-1(4-6)+1|1433|0−1(4−6)+1∣∣∣1433∣∣∣
Paso 1.3.2.2
Resta 66 de 44.
0-1⋅-2+1|1433|0−1⋅−2+1∣∣∣1433∣∣∣
0-1⋅-2+1|1433|0−1⋅−2+1∣∣∣1433∣∣∣
0-1⋅-2+1|1433|0−1⋅−2+1∣∣∣1433∣∣∣
Paso 1.4
Evalúa |1433|∣∣∣1433∣∣∣.
Paso 1.4.1
El determinante de una matriz 2×22×2 puede obtenerse usando la fórmula |abcd|=ad-cb∣∣∣abcd∣∣∣=ad−cb.
0-1⋅-2+1(1⋅3-3⋅4)0−1⋅−2+1(1⋅3−3⋅4)
Paso 1.4.2
Simplifica el determinante.
Paso 1.4.2.1
Simplifica cada término.
Paso 1.4.2.1.1
Multiplica 33 por 11.
0-1⋅-2+1(3-3⋅4)0−1⋅−2+1(3−3⋅4)
Paso 1.4.2.1.2
Multiplica -3−3 por 44.
0-1⋅-2+1(3-12)0−1⋅−2+1(3−12)
0-1⋅-2+1(3-12)0−1⋅−2+1(3−12)
Paso 1.4.2.2
Resta 1212 de 33.
0-1⋅-2+1⋅-90−1⋅−2+1⋅−9
0-1⋅-2+1⋅-90−1⋅−2+1⋅−9
0-1⋅-2+1⋅-90−1⋅−2+1⋅−9
Paso 1.5
Simplifica el determinante.
Paso 1.5.1
Simplifica cada término.
Paso 1.5.1.1
Multiplica -1−1 por -2−2.
0+2+1⋅-90+2+1⋅−9
Paso 1.5.1.2
Multiplica -9−9 por 11.
0+2-90+2−9
0+2-90+2−9
Paso 1.5.2
Suma 00 y 22.
2-92−9
Paso 1.5.3
Resta 99 de 22.
-7−7
-7−7
-7−7
Paso 2
Since the determinant is non-zero, the inverse exists.
Paso 3
Set up a 3×63×6 matrix where the left half is the original matrix and the right half is its identity matrix.
[011100142010334001]⎡⎢⎣011100142010334001⎤⎥⎦
Paso 4
Paso 4.1
Swap R2R2 with R1R1 to put a nonzero entry at 1,11,1.
[142010011100334001]⎡⎢⎣142010011100334001⎤⎥⎦
Paso 4.2
Perform the row operation R3=R3-3R1R3=R3−3R1 to make the entry at 3,13,1 a 00.
Paso 4.2.1
Perform the row operation R3=R3-3R1R3=R3−3R1 to make the entry at 3,13,1 a 00.
[1420100111003-3⋅13-3⋅44-3⋅20-3⋅00-3⋅11-3⋅0]⎡⎢⎣1420100111003−3⋅13−3⋅44−3⋅20−3⋅00−3⋅11−3⋅0⎤⎥⎦
Paso 4.2.2
Simplifica R3R3.
[1420100111000-9-20-31]⎡⎢⎣1420100111000−9−20−31⎤⎥⎦
[1420100111000-9-20-31]⎡⎢⎣1420100111000−9−20−31⎤⎥⎦
Paso 4.3
Perform the row operation R3=R3+9R2R3=R3+9R2 to make the entry at 3,23,2 a 00.
Paso 4.3.1
Perform the row operation R3=R3+9R2R3=R3+9R2 to make the entry at 3,23,2 a 00.
[1420100111000+9⋅0-9+9⋅1-2+9⋅10+9⋅1-3+9⋅01+9⋅0]⎡⎢⎣1420100111000+9⋅0−9+9⋅1−2+9⋅10+9⋅1−3+9⋅01+9⋅0⎤⎥⎦
Paso 4.3.2
Simplifica R3R3.
[1420100111000079-31]⎡⎢⎣1420100111000079−31⎤⎥⎦
[1420100111000079-31]⎡⎢⎣1420100111000079−31⎤⎥⎦
Paso 4.4
Multiply each element of R3R3 by 1717 to make the entry at 3,33,3 a 11.
Paso 4.4.1
Multiply each element of R3R3 by 1717 to make the entry at 3,33,3 a 11.
[14201001110007077797-3717]⎡⎢
⎢⎣14201001110007077797−3717⎤⎥
⎥⎦
Paso 4.4.2
Simplifica R3R3.
[14201001110000197-3717]⎡⎢
⎢⎣14201001110000197−3717⎤⎥
⎥⎦
[14201001110000197-3717]⎡⎢
⎢⎣14201001110000197−3717⎤⎥
⎥⎦
Paso 4.5
Perform the row operation R2=R2-R3R2=R2−R3 to make the entry at 2,32,3 a 00.
Paso 4.5.1
Perform the row operation R2=R2-R3R2=R2−R3 to make the entry at 2,32,3 a 00.
[1420100-01-01-11-970+370-1700197-3717]⎡⎢
⎢⎣1420100−01−01−11−970+370−1700197−3717⎤⎥
⎥⎦
Paso 4.5.2
Simplifica R2R2.
[142010010-2737-1700197-3717]⎡⎢
⎢⎣142010010−2737−1700197−3717⎤⎥
⎥⎦
[142010010-2737-1700197-3717]⎡⎢
⎢⎣142010010−2737−1700197−3717⎤⎥
⎥⎦
Paso 4.6
Perform the row operation R1=R1-2R3R1=R1−2R3 to make the entry at 1,31,3 a 00.
Paso 4.6.1
Perform the row operation R1=R1-2R3R1=R1−2R3 to make the entry at 1,31,3 a 00.
[1-2⋅04-2⋅02-2⋅10-2(97)1-2(-37)0-2(17)010-2737-1700197-3717]⎡⎢
⎢
⎢
⎢⎣1−2⋅04−2⋅02−2⋅10−2(97)1−2(−37)0−2(17)010−2737−1700197−3717⎤⎥
⎥
⎥
⎥⎦
Paso 4.6.2
Simplifica R1R1.
[140-187137-27010-2737-1700197-3717]⎡⎢
⎢
⎢⎣140−187137−27010−2737−1700197−3717⎤⎥
⎥
⎥⎦
[140-187137-27010-2737-1700197-3717]⎡⎢
⎢
⎢⎣140−187137−27010−2737−1700197−3717⎤⎥
⎥
⎥⎦
Paso 4.7
Perform the row operation R1=R1-4R2R1=R1−4R2 to make the entry at 1,21,2 a 00.
Paso 4.7.1
Perform the row operation R1=R1-4R2R1=R1−4R2 to make the entry at 1,21,2 a 00.
[1-4⋅04-4⋅10-4⋅0-187-4(-27)137-4(37)-27-4(-17)010-2737-1700197-3717]⎡⎢
⎢
⎢
⎢⎣1−4⋅04−4⋅10−4⋅0−187−4(−27)137−4(37)−27−4(−17)010−2737−1700197−3717⎤⎥
⎥
⎥
⎥⎦
Paso 4.7.2
Simplifica R1R1.
[100-1071727010-2737-1700197-3717]⎡⎢
⎢
⎢⎣100−1071727010−2737−1700197−3717⎤⎥
⎥
⎥⎦
[100-1071727010-2737-1700197-3717]⎡⎢
⎢
⎢⎣100−1071727010−2737−1700197−3717⎤⎥
⎥
⎥⎦
[100-1071727010-2737-1700197-3717]⎡⎢
⎢
⎢⎣100−1071727010−2737−1700197−3717⎤⎥
⎥
⎥⎦
Paso 5
The right half of the reduced row echelon form is the inverse.
[-1071727-2737-1797-3717]⎡⎢
⎢
⎢⎣−1071727−2737−1797−3717⎤⎥
⎥
⎥⎦
