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用初等变换求下列矩阵的逆矩阵:(12112310311-242-1-6)谢谢

题目详情
用初等变换求下列矩阵的逆矩阵:(1211 2310 311-2 42-1-6) 谢谢
▼优质解答
答案和解析
(A,E)=
1 2 1 1 1 0 0 0
2 3 1 0 0 1 0 0
3 1 1 -2 0 0 1 0
4 2 -1 -6 0 0 0 1

r4-2r2,r2-2r1,r3-3r1
1 2 1 1 1 0 0 0
0 -1 -1 -2 -2 1 0 0
0 -5 -2 -5 -3 0 1 0
0 -4 -3 -6 0 -2 0 1

r1+2r2,r2*(-1),r3+5r2,r4+4r2
1 0 -1 -3 -3 2 0 0
0 1 1 2 2 -1 0 0
0 0 3 5 7 -5 1 0
0 0 1 2 8 -6 0 1

r1+r4,r2-r4,r3-3r4
1 0 0 -1 5 -4 0 1
0 1 0 0 -6 5 0 -1
0 0 0 -1 -17 13 1 -3
0 0 1 2 8 -6 0 1

r1-r3,r4+2r3,r3*(-1)
1 0 0 0 22 -17 -1 4
0 1 0 0 -6 5 0 -1
0 0 0 1 17 -13 -1 3
0 0 1 0 -26 20 2 -5

r3r4
1 0 0 0 22 -17 -1 4
0 1 0 0 -6 5 0 -1
0 0 1 0 -26 20 2 -5
0 0 0 1 17 -13 -1 3

A^-1=
22 -17 -1 4
-6 5 0 -1
-26 20 2 -5 17 -13 -1 3