设`\alpha = (1,0,2,3),\beta = (3,4,5,1),A = \alpha ^T\beta`,则矩阵`A`的秩`R(A)`为( )
A. `1;`
B. `2;`
C. `3;`
D. `4.`
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已知三维向量组`\alpha_1,\alpha_2,\alpha_3`线性无关,则向量组`\alpha _1 - \alpha _2, \alpha _2 + k\alpha _3, \alpha _3 - \alpha _1`线性无关的充要条件是( )
A. `k=1;`
B. `k\ne 1;`
C. `k=-1;`
D. `k\ne -1.`
下列二阶矩阵可相似对角化的是 ( )
A. \[\left[ {\begin{array}{*20{c}}1&1\\ - 4&5\end{array}} \right];\]
B. \[\left[ {\begin{array}{*20{c}}1&-4\\1&5\end{array}} \right];\]
C. \[\left[ {\begin{array}{*20{c}}1&1\\ 0&0\end{array}} \right];\]
D. \[\left[ {\begin{array}{*20{c}}0&1\\ - 1&2\end{array}} \right].\]
若三阶方阵` A `的列向量组线性相关,且满足` | A + 2E | = | 2A - 3E | = 0 `,则` | 2A + 3E | = ` ( )
A. `0`;
B. `-9`;
C. `-18`;
D. `-27`。
设\[A = \left( {\begin{array}{*20{c}} 4& - 2& - 2\\ - 2&4&- 2\\ - 2&- 2&4 \end{array}} \right),B = \left( {\begin{array}{*20{c}} 1&0&0\\ 0&2&0\\ 0&0&0 \end{array}} \right),\] 则` A `与` B `( )
A. 一定相似;
B. 一定不相似;
C. 有可能相似;
D. 以上都不对。