用克莱姆法则解线性方程组x1+x2+x3=42x1-x2+x3=23x1+x2-x3=1过程要详细

Question

用克莱姆法则解线性方程组
x1+x2+x3=4
2x1-x2+x3=2
3x1+x2-x3=1
过程要详细

Answer 1

D = |(1,1,1),(2,-1,1),(3,1,-1)|= 10
D1 = |(4,2,1),(2,-1,1),(3,1,-1)|= 6
D2 = |(1,1,1),(4,2,1),(3,1,-1)|= 13
D3 = |(1,1,1),(2,-1,1),(4,4,1)|=21
x1 = D1/D = 3/5
x2 = D2/D = 13/10
x3 = D3/D = 21/10