一、题目
已知:
$$
\boldsymbol{A}=\left[\begin{array}{lll}
a_{11} & a_{12} & a_{13} \\
a_{21} & a_{22} & a_{23} \\
a_{31} & a_{32} & a_{33}
\end{array}\right]
$$
$$
\boldsymbol{B}=\left[\begin{array}{ccc}
a_{21} & a_{22} & a_{23} \\
a_{11} & a_{12} & a_{13} \\
a_{31}+a_{11} & a_{32}+a_{12} & a_{33}+a_{13}
\end{array}\right]
$$
$$
\boldsymbol{P}_{1}=\left[\begin{array}{lll}
0 & 1 & 0 \\
1 & 0 & 0 \\
0 & 0 & 1
\end{array}\right]
$$
$$
\boldsymbol{P}_{2}=\left[\begin{array}{ccc}
1 & 0 & 0 \\
0 & 1 & 0 \\
1 & 0 & 1
\end{array}\right]
$$
则必有:
(A) $A \boldsymbol{P}_{1} \boldsymbol{P}_{2}=\boldsymbol{B}$
(B) $\boldsymbol{A} \boldsymbol{P}_{2} \boldsymbol{P}_{1}=\boldsymbol{B}$
(C) $\boldsymbol{P}_{1} \boldsymbol{P}_{2} \boldsymbol{A}=\boldsymbol{B}$
(D) $\boldsymbol{P}_{2} \boldsymbol{P}_{1} \boldsymbol{A}=\boldsymbol{B}$
难度评级:
继续阅读“单位矩阵对矩阵的影响:左行右列,先近后远”