MCQ
If $A = \left[ \begin{array}{l}1\\2\\3\end{array} \right],$then $AA' = $
  • A
    $14$
  • B
    $\left[ \begin{array}{l}1\\4\\3\end{array} \right]$
  • $\left[ {\begin{array}{*{20}{c}}1&2&3\\2&4&6\\3&6&9\end{array}} \right]$
  • D
    None of these

Answer

Correct option: C.
$\left[ {\begin{array}{*{20}{c}}1&2&3\\2&4&6\\3&6&9\end{array}} \right]$
c
(c) $A' = [1\,\,2\,\,3]$, therefore $AA' = \left[ \begin{array}{l}1\\2\\3\end{array} \right]\left[ {1\,\,2\,\,3} \right] = \left[ {\begin{array}{*{20}{c}}1&2&3\\2&4&6\\3&6&9\end{array}} \right]$.

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