Question

高数矩阵谢谢

Answer 1

（1）A =
1 1 3 1
0 2 -1 2
2 -1 1 4
化为行最简矩阵
=
1 0 0 35/13
0 1 0 8/13
0 0 1 -10/13
于是：x1 = 35/13,x2 = 8/13,x3 = -10/13

（2）A =
0 1 2 1
1 1 4 2
1 -1 0 4
化为行最简矩阵
=
1 0 2 0
0 1 2 0
0 0 0 1
所以，方程组无解

（3）A =
1 -2 3 -1 2 2
3 -1 5 -3 -1 6
2 1 2 -2 -3 8
化为行最简矩阵
=
1 0 7/5 -1 -4/5 0
0 1 -4/5 0 -7/5 0
0 0 0 0 0 1
所以，方程组无解

（4）A =
1 1 2 4 3
3 1 6 2 3
-1 2 -2 1 1
化为行最简矩阵
=
1 0 2 0 1/2
0 1 0 0 1/2
0 0 0 1 1/2
所以：方程组有无穷多解
x1 = 1/2 - 2x3
x2 = 1/2
x3 = 1/2