`\alpha _j`为四阶行列式D的第j列,(j=1,2,3,4,),且D=-5,则下列行列式中,等于-10的是( )
A. \[\left| {2{\alpha _1},2{\alpha _2},2{\alpha _3},2{\alpha _4}} \right|\]
B. \[\left| {{\alpha _1} + {\alpha _2},{\alpha _2} + {\alpha _3},{\alpha _3} + {\alpha _4},{\alpha _4} + {\alpha _1}} \right|\]
C. \[\left| {{\alpha _1},{\alpha _1} + {\alpha _2},{\alpha _1} + {\alpha _2} + {\alpha _3},{\alpha _1} + {\alpha _2} + {\alpha _3} + {\alpha _4}} \right|\]
D. \[\left| {{\alpha _1} + {\alpha _2},{\alpha _2} + {\alpha _3},{\alpha _3} + {\alpha _4},{\alpha _4} - {\alpha _1}} \right|\]
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设多项式\[f(x) = \left| {\begin{array}{*{20}{c}} x&2&3&4\\ x&x&x&3\\ 1&0&2&x\\ x&1&3&x \end{array}} \right|\],则多项式的次数为( )
A. 2
B. 3
C. 4
D. 5
\[{D_5} = \left| {\begin{array}{*{20}{c}} {1 - a}&a&0&0&0\\ { - 1}&{1 - a}&a&0&0\\ 0&{ - 1}&{1 - a}&a&0\\ 0&0&{ - 1}&{1 - a}&a\\ 0&0&0&{ - 1}&{1 - a} \end{array}} \right| = \]( )
A. \[1 - a + {a^2} - {a^3} + {a^4} - {a^5}\]
B. \[1 + a + {a^2} - {a^3} + {a^4} - {a^5}\]
C. \[1 - a + {a^2} + {a^3} + {a^4} - {a^5}\]
D. \[1 + a + {a^2} + {a^3} + {a^4} + {a^5}\]
设3阶矩阵\[A = \left[ {\begin{array}{*{20}{c}} a&b&b\\ b&a&b\\ b&b&a \end{array}} \right]\],若`\A`的伴随矩阵的秩为1,则必有 ( )
A. \[a = b\]
B. \[a + 2b = 0\]
C. `\a = b`或`\a + 2b = 0`
D. 若`\a \ne b`且`\a + 2b = 0`
设\[{A^{ - 1}} = \left[ {\begin{array}{*{20}{c}} 1&1&1\\ 1&2&3\\ 1&4&9 \end{array}} \right]\],则`\| A|`的各元素代数余子式之和为 ( )
A. 46
B. 23
C. \[\frac{{23}}{2}\]
D. -23