1 2 2 2 2 3 1 2 1 1 1-1 1 0-2-6 用初等变换法求矩阵逆,
2个回答

(A,E)=

1 2 2 2 1 0 0 0

2 3 1 2 0 1 0 0

1 1 1 -1 0 0 1 0

1 0 -2 -6 0 0 0 1

r1-r3,r2-2r3,r4-r3

0 1 1 3 1 0 -1 0

0 1 -1 4 0 1 -2 0

1 1 1 -1 0 0 1 0

0 -1 -3 -5 0 0 -1 1

r2-r1,r3-r1,r4+r1

0 1 1 3 1 0 -1 0

0 0 -2 1 -1 1 -1 0

1 0 0 -4 -1 0 2 0

0 0 -2 -2 1 0 -2 1

r2-r4,r4*(-1/2),r1-r4

0 1 0 2 3/2 0 -2 1/2

0 0 0 3 -2 1 1 -1

1 0 0 -4 -1 0 2 0

0 0 1 1 -1/2 0 1 -1/2

r2*(1/3),r1-2r2,r3+4r2,r4-r2

0 1 0 0 17/6 -2/3 -8/3 7/6

0 0 0 1 -2/3 1/3 1/3 -1/3

1 0 0 0 -11/3 4/3 10/3 -4/3

0 0 1 0 1/6 -1/3 2/3 -1/6

交换行

1 0 0 0 -11/3 4/3 10/3 -4/3

0 1 0 0 17/6 -2/3 -8/3 7/6

0 0 1 0 1/6 -1/3 2/3 -1/6

0 0 0 1 -2/3 1/3 1/3 -1/3

A^-1 =

-11/3 4/3 10/3 -4/3

17/6 -2/3 -8/3 7/6

1/6 -1/3 2/3 -1/6

-2/3 1/3 1/3 -1/3