Question

矩阵是初等行变换问题（怎么变成下面那样?）

Answer 1

2-r1,r3-r1

1 1 1 1 0 0

0 1 0 -1 1 0

0 0 2 -1 0 1

r3*(1/2)

1 1 1 1 0 0

0 1 0 -1 1 0

0 0 1 -1/2 0 1/2

r1-r2-r3

1 0 0 5/2 -1 -1/2

0 1 0 -1 1 0

0 0 1 -1/2 0 1/2