题目内容

设 $A=\left(\begin{array}{ccc}1 & 2 & -1 \\ 3 & 4 & -2 \\ 5 & -4 & 1\end{array}\right),$ 则 $A^{-1}=$ ( ).

A. $ \left(\begin{array}{ccc}-2 & \displaystyle \frac{13}{2} & -16 \\ -1 & 3 & -7 \\ 0 &\displaystyle \frac{1}{2} & -1\end{array}\right)$.
B. $\left(\begin{array}{ccc}-2 & -1 & 0 \\ \displaystyle \frac{13}{2} & 3 & \displaystyle \frac{1}{2} \\ -16 & -7 & -1\end{array}\right)$.
C. $ \left(\begin{array}{ccc}-2 & \displaystyle -\frac{13}{2} & -16 \\ 1 & 3 & 7 \\ 0 &\displaystyle -\frac{1}{2} & -1\end{array}\right)$.
D. $\left(\begin{array}{ccc}-2 & 1 & 0 \\ \displaystyle -\frac{13}{2} & 3 & \displaystyle -\frac{1}{2} \\ -16 & 7 & -1\end{array}\right)$.

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设 $A=\left(\begin{array}{ccc}1 & 2 & -1 \\ 3 & 4 & -2 \\ 5 & -4 & 1\end{array}\right),$ 则 $A$ 的伴随矩阵 $A^*=$ ( ).

A. $\left(\begin{array}{ccc}-4 & -13 & -32 \\ 2 & 6 & 14 \\ 0 & -1 & -2\end{array}\right)$
B. $\left(\begin{array}{ccc}-4 & 2 & 0 \\ -13 & 6 & -1 \\ -32 & 14 & -2\end{array}\right)$
C. $\left(\begin{array}{ccc}-4 & 13 & -32 \\ -2 & 6 & -14 \\ 0 & 1 & -2\end{array}\right)$
D. $\left(\begin{array}{ccc}-4 & -2 & 0 \\ 13 & 6 & 1 \\ -32 & -14 & -2\end{array}\right)$

设 $A=\left(\begin{array}{ccc}1 & 2 & -1 \\ 3 & 4 & -2 \\ 5 & -4 & 1\end{array}\right),$ 则 $|A|=$______ .

设 $A=\left(\begin{array}{ccc}1 & 2 & -1 \\ 3 & 4 & -2 \\ 5 & -4 & 1\end{array}\right),$ 则 $A$ 是否可逆?

A. 可逆
B. 不可逆

已知 $ A=(1,1,0,2)$, $B=(4,-1,2,1)^T,$ 则 $A^T B^T=$ ( ).

A. $(5)$
B. $\left(\begin{array}{c}4 \\ -1 \\ 0 \\2 \end{array}\right)$
C. $\left(\begin{array}{cccc}4 & -1 & 2 & 1 \\ 4 & -1 & 2 & 1 \\ 0 & 0 & 0 & 0 \\ 8 & -2 & 4 & 2\end{array}\right)$
D. $(4,-1,0,2)$

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