A =
[ 2 1 -2]
[ 0 1 2]
[ 0 -1 1]
|A|= 6
A*B =2A(-1)+2B
左乘A:6B=2E+2AB
(6E-2A)B=2E
B=(3E-A)^(-1)=
[ 1 2/3 -1/3]
[ 0 1/3 1/3]
[ 0 -1/6 1/3]
A =
[ 2 1 -2]
[ 0 1 2]
[ 0 -1 1]
|A|= 6
A*B =2A(-1)+2B
左乘A:6B=2E+2AB
(6E-2A)B=2E
B=(3E-A)^(-1)=
[ 1 2/3 -1/3]
[ 0 1/3 1/3]
[ 0 -1/6 1/3]