设3阶矩阵`\A = (alpha _1,alpha _2,alpha _3),B = (alpha _2-2alpha _3,alpha _1,alpha _2)`,若`\A`的行列式`\| A | = 2`,则`\ B `的行列式`\| B |= ` ( )
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设`\A`为`\n`阶方阵,`\A^**`为`\A`的伴随矩阵,且`\| A | = a \ne 0`,则`\| A^**| = ` ( )
A. \[a^{n - 1}\]
B. \[a^n \]
C. \[a^{n + 1}\]
D. \[a^{n + 2}\]
设`\n`阶方阵`\A`经过初等变换后得方阵`\B`,则 ( )
A. \[\left| {\rm{A}} \right| = \left| {\rm{B}} \right|\]
B. \[\left| A \right| \ne \left| B \right|\]
C. \[\left| A \right|\left| B \right| \ge {\rm{0}}\]
D. 若`\| A| = 0`,则`\| B| = 0`
设`\A,B`为`\n`阶矩阵,`\| A | = 2,| B | = - 3`,则`\| | 2A^** || B^T|| = ` ( )
A. \[3 \cdot {2^{2{n^2} + n}}\]
B. \[ - 3 \cdot {2^{2{n^2} + n}}\]
C. \[3 \cdot {2^{2{n^2} - n}}\]
D. \[ - 3 \cdot {2^{2{n^2} - n}}\]
设\[A = \left( {\begin{array}{*{20}{c}} a&b&b\\ b&a&b\\ b&b&a \end{array}} \right)\],`\ A`的伴随阵的秩为1,则( )
A. `\a = b`或`\a + 2b = 0`
B. `\a \ne b`且`\a + 2b = 0`
C. `\a = b`或`\a + 2b \ne 0`
D. `\a \ne b`且`\a + 2b \ne 0`