写出增广矩阵为1 1 -3 -1 13 -1 -3 4 31 5 -9 -8 1 r2-3r1,r3-r1~1 1 -3 -1 10 -4 6 7 00 4 -6 -7 0 r2+r3,r1-r3/4,交换行次序~1 0 -3/2 3/4 10 1 -3/2 -7/4 00 0 0 0 0 分别令后两列为(2,0)^T和(0,4)^T于是得到解为k1(3,3,2,0)^T+k2(-3,7,0,4)^T+(1,0,0,0)^T