Question

写出方程组2*x1+x2-x3+x4=1,x1+2*x2+x3-x4=2,x1+x2+2*x3+x4=3的通解?

Answer 1

2*x1+x2-x3+x4=1,①x1+2*x2+x3-x4=2,②x1+x2+2*x3+x4=3.③（①+②）/3,x1+x2=1,x1=1-x2④②+③,2x1+3x2+3x3=5,⑤把④代入⑤,x2+3x3=3,令x3=m,m为任意数,则x2=3-3m,代入④,x1=3m-2,代入①,x4=2-2m,∴通解是（3m-2,3-3...