行列式的性质 例2 设A为n阶方阵，a为n×1矩阵，B为1×n矩阵，已知 Aa =0,试证 B 6 明： =(c-b)Al. 例3 设3阶方阵4的列分块表示为4三(@1,2.0,4=5 若B=(0+24,3可+40.502试求B 4口卡6，·2,4元，至风0 张莉(Tongji University】 线性代数 8/601™5ü ~2 Aènê , αèn × 1 › , βè1 × n › ßÆ      A α β b      = 0, £y ²µ      A α β c      = (c − b)|A|. ~3 3ê A ©¨L´èA = (α1, α2, α3), |A| = 5, eB = (α1 + 2α2, 3α1 + 4α3, 5α2), £¶|B|. ‹s (Tongji University) Ç 5 ì Í 8 / 60