克莱姆法则nnnnnnnnnnbaxaxxabaxaxxabaxaxxa22112222212111212111线性方程组112201()(1,2,,)如果它的系数行列式,则它有唯一解jjjjnnjDDxbAbAbAjnDD12nbbbb12nxxx,x111212122212nnnnnnaaaaaaA,aaa证明:将方程组写为的两边左乘-1,...