1.用消元法解线性方程组.-|||- ) (x)_(1)+2(x)_(2)+(x)_(3)=3, -2(x)_(1)+(x)_(2)-(x)_(3)=-3 (x)_(1)-4(x)_(2)+2(x)_(3)=-5 .

用消元法解线性方程组 ) (x)_(1)+2(x)_(3)-4(x)_(3)=1 (x)_(2)+(x)_(3)=0 -(x)_(3)=2 .用消元法解线性

1.用消元法解下列线性方程组:-|||-(3) ) (x)_(1)-(x)_(2)+(x)_(3)-(x)_(4)=1 (x)_(1)-(x)_(2)-(x

解线性方程组_(1)-2(x)_(2)+(x)_(3)=-2-|||-__ __-|||-(x)_(1)+(x)_(2)-3(x)_(3)=1-|||--(x)

线性方程组 ) (x)_(1)+2(x)_(2)-2(x)_(3)=1 2(x)_(1)+4(x)_(2)-4(x)_(3)=2 3(x)_(1)+6(x)_

给定线性方程组 ) (x)_(1)+(x)_(2)+(x)_(3)=a-3 (x)_(1)+a(x)_(2)+(x)_(3)=-2 (x)_(1)+(x)_(

对于线性方程组 ) 2(x)_(1)+3(x)_(2)=-1 (x)_(1)-2(x)_(2)=3 .对于线性方程组，下列错误的选项是。系数行列式为该方程组

3.求解线性方程组 ) (x)_(1)+2(x)_(2)-(x)_(3)+2(x)_(4)=1 2(x)_(1)+4(x)_(2)+(x)_(3)+(x)_(

9.用改进平方根法解线性方程组-|||- ) 2(x)_(1)-(x)_(2)+(x)_(3)=4, -(x)_(1)-2(x)_(2)+3(x)_(3)=5

5.线性方程组 ) (x)_(1)-(x)_(2)=(a)_(1) 2(x)_(2)-(x)_(3)=(a)_(2) (x)_(1)+(x)_(2)-(x)

如果线性方程组 ) 3(x)_(1)+k(x)_(2)-(x)_(3)=1 4(x)_(2)-(x)_(3)=2 4(x)_(2)+k(x)_(3)=3 .