写出向量组为 1 0 3 1 2-1 3 0 -2 1 2 1 7 2 5 r2+r1,r3-2r1~1 0 3 1 20 3 3 -1 3 0 1 1 0 1 r2-3r2~1 0 3 1 20 0 0 -1 0 0 1 1 0 1 r1+r2,r2*(-1),交换r2和r3~1 0 3 0 20 1 1 0 10 0 0 1 0 于是极大无关组为a1,a2,a4而a3=3a1+a2,a5=2a1+a2