Let the matrix A and B be defined as A , = , [ * 20 c 3&2 2&1 ] a… - Vidyadip

MCQ

Let the matrix $A$ and $B$ be defined as $A\, = \,\left[ {\begin{array}{*{20}{c}}
3&2 \\
2&1
\end{array}} \right]$ and $B\, = \,\left[ {\begin{array}{*{20}{c}}
3&1 \\
7&3
\end{array}} \right]$ , then the value of $det. \,(2A^9B^{-1}),$ is :-

A
$2$
B
$1$
C
$-1$
✓
$-2$

✓

Answer

Correct option: D.

$-2$

d
$|A|=-1,|B|=2$

$\left| {2{A^9}{B^{ - 1}}} \right| = 4|A{|^9}|B{|^{ - 1}} = - 2$

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