MCQ
$\left[ \begin{array}{l}\,\,\,1\\ - 1\\\,\,\,2\end{array} \right]\,\,[2{\rm{ }}\,\,1{\rm{ }} - 1]$ =
  • A
    $[-1]$
  • B
    $\left[ \begin{array}{l}\,\,\,2\\ - 1\\ - 2\end{array} \right]$
  • $\left[ {\begin{array}{*{20}{c}}{\,\,2}&{\,\,1}&{ - 1}\\{ - 2}&{ - 1}&{\,\,1}\\{\,\,4}&{\,\,2}&{ - 2}\end{array}} \right]$
  • D
    Not defined

Answer

Correct option: C.
$\left[ {\begin{array}{*{20}{c}}{\,\,2}&{\,\,1}&{ - 1}\\{ - 2}&{ - 1}&{\,\,1}\\{\,\,4}&{\,\,2}&{ - 2}\end{array}} \right]$
c
(c)$\left[ {\begin{array}{*{20}{c}}{\,\,1}\\{ - 1\,}\\{\,\,2}\end{array}} \right]\,\,[\begin{array}{*{20}{c}}2&1&{ - 1}\end{array}] = \left[ {\begin{array}{*{20}{c}}2&1&{ - 1}\\{ - 2\,\,\,}&{ - 1\,\,\,}&{\,\,1}\\4&2&{ - 2}\end{array}} \right]$.

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