题目内容

已知`\vec\alpha _1,\vec\alpha _2,\vec\beta _1,\vec\beta _2`是3维列向量,设`\A = [\vec\alpha _1,\vec\alpha _2,\vec\beta _1],B = [\vec\alpha _1,\vec\alpha _2,\vec\beta _2],| A | = 2,| B | = 3`, 则行列式`\| 2A - B| = ` ( )

A. -1
B. 0
C. 1
D. 2

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已知行列式\[D = \left| {\begin{array}{*{20}{c}} 1&2&3&5\\ 2&1&2&1\\ 1&4&0&5\\ {10}&{ - 2}&1&3 \end{array}} \right|\],其中`\A_{ij}`表示`\A`的第`\i`行第`\j`列元素的代数余子式。则`\A_{11}- 2A_{21} - A_{31} + 10A_{41} = ` ( )

A. 52
B. 53
C. 54
D. 55

在四阶行列式`\Delta (a_{ij})`中含`\a_{32}a_{14}a_{21}`的项是 ( )

A. `\a_{14}a_{21}a_{32}a_{43}`
B. `\a_{14}a_{22}a_{31}a_{43}`
C. `\-a_{14}a_{21}a_{32}a_{43}`
D. `\-a_{14}a_{22}a_{31}a_{43}`

`\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. \[\left| {{\alpha _1} + {\alpha _2},{\alpha _2} + {\alpha _3},{\alpha _3} + {\alpha _4},{\alpha _4} - {\alpha _1}} \right|\]

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

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