(1)A为n阶可逆方阵,α,β为n维列向量,求证:det(A+αβT)=(1+βTA-1α)det(A) (2)设A=(aij)n×r满足rank(A)=r,求证:det(ATA)≠0
问题描述:
(1)A为n阶可逆方阵,α,β为n维列向量,求证:det(A+αβT)=(1+βTA-1α)det(A) (2)设A=(aij)n×r满足rank(A)=r,求证:det(ATA)≠0
答
(1)A为n阶可逆方阵,α,β为n维列向量,求证:det(A+αβT)=(1+βTA-1α)det(A) (2)设A=(aij)n×r满足rank(A)=r,求证:det(ATA)≠0