c4-2c3,c3-2c2,c5-c2
0 1 0 0 0
2 0 1 -1 3
-1 3 -1 -8 3
3 4 -5 -1 -4
1 1 -1 4 5
按第2列展开,D= -1*
2 1 -1 3
-1 -1 -8 3
3 -5 -1 -4
1 -1 4 5
r1+2r2,r3+3r2,r4+r2
0 -1 -17 9
-1 -1 -8 3
0 -8 -25 5
0 -2 -4 8
按第1列展开
-1 -17 9
-8 -25 5
-2 -4 8
c3+4c1,c2-2c1
-1 -15 5
-8 -9 -27
-2 0 0
按第3行展开 D=2*
-15 5
-9 -27
= 2*(15*27 + 5*9)
= 900.