## 选项

[A].   当 $k$ $>$ $0$ 时行列式变号，当 $k$ $<$ $0$ 时行列式不变号

[B].   当 $k$ $<$ $0$ 时行列式变号，当 $k$ $>$ $0$ 时行列式不变号

[C].   行列式变号

[D].   行列式的值不变

## 选项

[A].   该行列式不等于 $0$

[B].   该行列式等于 $1$

[C].   该行列式等于 $0$

[D].   该行列式不等于 $1$

## 选项

[A].   该行列式不等于 $0$

[B].   该行列式等于 $1$

[C].   该行列式等于 $0$

[D].   该行列式不等于 $1$

## 选项

[A].   该行列式不等于 $0$

[B].   该行列式等于 $1$

[C].   该行列式等于 $0$

[D].   该行列式不等于 $1$

## 问题

$\left|\begin{array}{lll} a_{11}+b_{11} & a_{12} & a_{13} \\ a_{21}+b_{21} & a_{22} & a_{23} \\ a_{31}+b_{31} & a_{32} & a_{33} \end{array}\right|$.

## 选项

[A].   $\left|\begin{array}{lll} a_{11}+b_{11} & a_{12} & a_{13} \\ a_{21}+b_{21} & a_{22} & a_{23} \\ a_{31}+b_{31} & a_{32} & a_{33} \end{array}\right|$ $=$ $\left|\begin{array}{lll} a_{11} & a_{12} & a_{13} \\ a_{21} & a_{22} & a_{23} \\ a_{31} & a_{32} & a_{33} \end{array}\right|$ $\times$ $\left|\begin{array}{lll} b_{11} & a_{12} & a_{13} \\ b_{21} & a_{22} & a_{23} \\ b_{31} & a_{32} & a_{33}\end{array}\right|$

[B].   $\left|\begin{array}{lll} a_{11}+b_{11} & a_{12} & a_{13} \\ a_{21}+b_{21} & a_{22} & a_{23} \\ a_{31}+b_{31} & a_{32} & a_{33} \end{array}\right|$ $=$ $\left|\begin{array}{lll} a_{11} & a_{12} & a_{13} \\ a_{21} & a_{22} & a_{23} \\ a_{31} & a_{32} & a_{33} \end{array}\right|$ $-$ $\left|\begin{array}{lll} b_{11} & a_{12} & a_{13} \\ b_{21} & a_{22} & a_{23} \\ b_{31} & a_{32} & a_{33}\end{array}\right|$

[C].   $\left|\begin{array}{lll} a_{11}+b_{11} & a_{12} & a_{13} \\ a_{21}+b_{21} & a_{22} & a_{23} \\ a_{31}+b_{31} & a_{32} & a_{33} \end{array}\right|$ $=$ $\left|\begin{array}{lll} a_{11} & a_{12} & a_{13} \\ a_{21} & a_{22} & a_{23} \\ a_{31} & a_{32} & a_{33} \end{array}\right|$ $+$ $\left|\begin{array}{lll} b_{11} & a_{12} & a_{13} \\ b_{21} & a_{22} & a_{23} \\ b_{31} & a_{32} & a_{33}\end{array}\right|$

[D].   $\left|\begin{array}{lll} a_{11}+b_{11} & a_{12} & a_{13} \\ a_{21}+b_{21} & a_{22} & a_{23} \\ a_{31}+b_{31} & a_{32} & a_{33} \end{array}\right|$ $=$ $\left|\begin{array}{lll} \frac{1}{a_{11}} & a_{12} & a_{13} \\ \frac{1}{a_{21}} & a_{22} & a_{23} \\ \frac{1}{a_{31}} & a_{32} & a_{33} \end{array}\right|$ $+$ $\left|\begin{array}{lll} \frac{1}{b_{11}} & a_{12} & a_{13} \\ \frac{1}{b_{21}} & a_{22} & a_{23} \\ \frac{1}{b_{31}} & a_{32} & a_{33}\end{array}\right|$

$\left|\begin{array}{lll} \textcolor{Red}{a_{11}} \textcolor{yellow}{+} \textcolor{cyan}{b_{11}} & a_{12} & a_{13} \\ \textcolor{Red}{a_{21}} \textcolor{yellow}{+} \textcolor{cyan}{b_{21}} & a_{22} & a_{23} \\ \textcolor{Red}{a_{31}} \textcolor{yellow}{+} \textcolor{cyan}{b_{31}} & a_{32} & a_{33} \end{array}\right|$ $=$ $\left|\begin{array}{lll} \textcolor{Red}{a_{11}} & a_{12} & a_{13} \\ \textcolor{Red}{a_{21}} & a_{22} & a_{23} \\ \textcolor{Red}{a_{31}} & a_{32} & a_{33} \end{array}\right|$ $\textcolor{yellow}{+}$ $\left|\begin{array}{lll} \textcolor{cyan}{b_{11}} & a_{12} & a_{13} \\ \textcolor{cyan}{b_{21}} & a_{22} & a_{23} \\ \textcolor{cyan}{b_{31}} & a_{32} & a_{33}\end{array}\right|$

## 选项

[A].   $\left|\begin{array}{cccc} a_{11} & a_{12} & \cdots & a_{1 n} \\ \cdots & \cdots & \cdots & \cdots \\ k a_{i 1} & k a_{i 2} & \cdots & k a_{i n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{n 1} & a_{n 2} & \cdots & a_{n n} \end{array}\right|$ $=$ $-k$ $\left|\begin{array}{cccc} a_{11} & a_{12} & \cdots & a_{1 n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{i 1} & a_{i 2} & \cdots & a_{i n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{n 1} & a_{n 2} & \cdots & a_{n n}\end{array}\right|$

[B].   $\left|\begin{array}{cccc} a_{11} & a_{12} & \cdots & a_{1 n} \\ \cdots & \cdots & \cdots & \cdots \\ k a_{i 1} & k a_{i 2} & \cdots & k a_{i n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{n 1} & a_{n 2} & \cdots & a_{n n} \end{array}\right|$ $=$ $k^{n}$ $\left|\begin{array}{cccc} a_{11} & a_{12} & \cdots & a_{1 n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{i 1} & a_{i 2} & \cdots & a_{i n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{n 1} & a_{n 2} & \cdots & a_{n n}\end{array}\right|$

[C].   $\left|\begin{array}{cccc} a_{11} & a_{12} & \cdots & a_{1 n} \\ \cdots & \cdots & \cdots & \cdots \\ k a_{i 1} & k a_{i 2} & \cdots & k a_{i n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{n 1} & a_{n 2} & \cdots & a_{n n} \end{array}\right|$ $=$ $\frac{1}{k}$ $\left|\begin{array}{cccc} a_{11} & a_{12} & \cdots & a_{1 n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{i 1} & a_{i 2} & \cdots & a_{i n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{n 1} & a_{n 2} & \cdots & a_{n n}\end{array}\right|$

[D].   $\left|\begin{array}{cccc} a_{11} & a_{12} & \cdots & a_{1 n} \\ \cdots & \cdots & \cdots & \cdots \\ k a_{i 1} & k a_{i 2} & \cdots & k a_{i n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{n 1} & a_{n 2} & \cdots & a_{n n} \end{array}\right|$ $=$ $k$ $\left|\begin{array}{cccc} a_{11} & a_{12} & \cdots & a_{1 n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{i 1} & a_{i 2} & \cdots & a_{i n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{n 1} & a_{n 2} & \cdots & a_{n n}\end{array}\right|$

$\left|\begin{array}{cccc} a_{11} & a_{12} & \cdots & a_{1 n} \\ \cdots & \cdots & \cdots & \cdots \\ \textcolor{red}{k} a_{i 1} & \textcolor{red}{k} a_{i 2} & \cdots & \textcolor{red}{k} a_{i n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{n 1} & a_{n 2} & \cdots & a_{n n} \end{array}\right|$ $=$ $\textcolor{red}{k}$ $\left|\begin{array}{cccc} a_{11} & a_{12} & \cdots & a_{1 n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{i 1} & a_{i 2} & \cdots & a_{i n} \\ \cdots & \cdots & \cdots & \cdots \\ a_{n 1} & a_{n 2} & \cdots & a_{n n}\end{array}\right|$

## 选项

[A].   $D$ $=$ $D^{T}$

[B].   $D$ $=$ $2 D^{T}$

[C].   $D$ $\neq$ $D^{T}$

[D].   $D$ $=$ $- D^{T}$

$D$ $=$ $D^{T}$