If A = [ * 20 c 1&0&0 2&1&0 - 3 &2&1 ] , and B = [ * 20 c 1&0&0 -… - Vidyadip

MCQ

If $A = \left[ {\begin{array}{*{20}{c}}
1&0&0 \\
2&1&0 \\
{ - 3}&2&1
\end{array}} \right]\,$ and $B = \left[ {\begin{array}{*{20}{c}}
1&0&0 \\
{ - 2}&1&0 \\
7&{ - 2}&1
\end{array}} \right]$ then $AB$ equals

✓
$I$
B
$A$
C
$B$
D
$0$

✓

Answer

Correct option: A.

$I$

a
$A = \left[ {\begin{array}{*{20}{c}}
1&0&0\\
2&1&0\\
{ - 3}&2&1
\end{array}} \right],B = \left[ {\begin{array}{*{20}{c}}
1&0&0\\
{ - 2}&1&0\\
7&{ - 2}&1
\end{array}} \right]$

$AB = \left[ {\begin{array}{*{20}{c}}
1&0&0\\
0&1&0\\
0&0&1
\end{array}} \right] = I$

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