用克莱姆法则解下列关於x.y.z的方程组4x-y-2x=4,2x+y-4z=8,x+2y+z=1
问题描述:
用克莱姆法则解下列关於x.y.z的方程组4x-y-2x=4,2x+y-4z=8,x+2y+z=1
答
4 -1 -2
D= 2 1 -4 =20
1 2 1
4 -1 -2
D1= 8 1 -4 =18
1 2 1
4 4 -2
D2=2 8 -4 =16
1 1 1
4 -1 4
D3= 2 1 8 =-54
1 2 1
x=D1/D=0.9 y=D2/D=0.8 z=D3/D=-2.7