求线性方程组一般解2x1+x^2-x3+x4=13x1-2x^3+x3-3x4=4x1+4x^2-3x3+5x4=-2

增广矩阵 =
2 1 -1 1 1
3 -2 1 -3 4
1 4 -3 5 -2
r2-r1-r3,r1-2r3
0 -7 5 -9 5
0 -7 5 -9 5
1 4 -3 5 -2
r2-r1,r1*(-1/7),r3-4r1
0 1 -5/7 9/7 -5/7
0 0 0 0 0
1 0 -1/7 -1/7 6/7
交换行
1 0 -1/7 -1/7 6/7
0 1 -5/7 9/7 -5/7
0 0 0 0 0
通解为:(6/7,-5/7,0,0)'+c1(1,5,7,0)'+c2(1,-9,0,7)