初等变换求逆距阵b=[1 2 3][2 2 1][3 4 3]

[1 2 3 1 0 0] [1 2 3 1 0 0]
[2 2 1 0 1 0] ==> [0 -2 -5 -2 -1 0]==>
[3 4 3 0 0 1] [0 -2 -6 -3 0 1]
[ 1 2 3 1 0 0 ] [1 0 -2 -1 1 0 ]
[ 0 -2 -5 -2 1 0 ]==>[0 -2 0 3 6 5 ]==>
[ 0 0 -1 -1 -1 1 ] [0 0 -1 -1 -1 1 ]
[1 0 0 0 2 -1 ] [ 1 0 0 0 2 - 1 ]
[0 -2 0 3 6 -5 ] ==> [ 0 1 0 -3/2 -3 5/2 ]
[0 0 -1 -1 -1 1 ] [ 0 0 1 1 1 -1 ]
即逆距阵：
[ 0 2 - 1]
[ -3/2 -3 5/2 ]
[ 1 1 -1 ]
自己再算算!