题目内容

变化规律(1)转置后秩变大(2)r(A)<=min(m,n),A是m*n型矩阵(3)r(kA)=r(A),k不等于0(4)r(A)=0 <=> A=0(5)r(A+B)<=r(A)+r(B)(6)r(AB)<=min(r(A),r(B))(7)r(A)+r(B)-n<=r(AB)

A. 对
B. 错

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