(A,E)=
0 0 2 1 0 0
0 3 0 0 1 0
4 0 0 0 0 1
r1*(1/2),r2*(1/3),r3*(1/4)
0 0 1 1/2 0 0
0 1 0 0 1/3 0
1 0 0 0 0 1/4
r1r3
1 0 0 0 0 1/4
0 1 0 0 1/3 0
0 0 1 1/2 0 0
所以 A^-1 =
0 0 1/4
0 1/3 0
1/2 0 0
(A,E)=
0 0 2 1 0 0
0 3 0 0 1 0
4 0 0 0 0 1
r1*(1/2),r2*(1/3),r3*(1/4)
0 0 1 1/2 0 0
0 1 0 0 1/3 0
1 0 0 0 0 1/4
r1r3
1 0 0 0 0 1/4
0 1 0 0 1/3 0
0 0 1 1/2 0 0
所以 A^-1 =
0 0 1/4
0 1/3 0
1/2 0 0