第1个回答 2011-12-14
1 5 -1 -1 -1
1 -2 1 3 3
3 8 -1 1 1
1 -9 3 7 7
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1 5 -1 -1 -1
0 -7 2 4 4
0 -7 2 4 4
0-14 4 8 8
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1 5 -1 -1 -1
0 -7 2 4 4
0 0 0 0 0
0 0 0 0 0
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1 5 -1 -1 -1
0 -7/2 1 2 2
0 0 0 0 0
0 0 0 0 0
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1 -3/2 0 1 1
0 -7/2 1 2 2
0 0 0 0 0
0 0 0 0 0
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故有
x1=3/2x2-x4+1
x3=7/2x2-2x4+2本回答被提问者采纳