题目内容

设A为n阶实矩阵，AT为A的转置矩阵，则对于线性方程组(I)AX＝0和(Ⅱ)ATAx＝0必有()．

A. (Ⅱ)的解是(I)的解，但(I)的解不是(Ⅱ)的解
B. (Ⅱ)的解是(I)的解，(I)的解也是(Ⅱ)的解
C. (I)的解不是(Ⅱ)的解，(Ⅱ)的解也不是(I)的解
D. (I)的解是(Ⅱ)的解，但(Ⅱ)的解不是(I)的解

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