100
=a1a2 an
0010 0001 0 000 0000 1
a1 1 1a2 1a3 1an 1
ni=1
000 001+∑ai 1
=(a1a2 an)(1+∑1.
i=1ai
8.用克莱姆法则解下列方程组: x1+x2+x3+x4=5 x+2x2 x3+4x4= 2(1) 1;
2x1 3x2 x3 5x4= 2 3x+x+2x+11x=0 1234解因为
1D=12
3
12 31
1 1 12
1
4= 142, 511
14= 142,D=2 52
113
5
2 20
1 1 12
1
4= 284, 511
n
52D1= 20D3=2
3
所以
12 311 1 12
12 315 2 20114= 426,D=1
42 5
1131
2 311 1 125
2=142, 20
x1=
DDDD
=1,x2==2,x3==3,x4== 1.DDDD