MCQ
If $A = \left[ {\begin{array}{*{20}{c}}1&2&3\\5&0&7\\6&2&5\end{array}} \right]$and $B = \left[ {\begin{array}{*{20}{c}}1&3&5\\0&0&2\end{array}} \right]$, then which of the following is defined
  • A
    $AB$
  • B
    $A + B$
  • $A'B'$
  • D
    $B'A'$

Answer

Correct option: C.
$A'B'$
c
(c) By inspection, $A'$is a matrix of order $3 \times 3$ and $B'$is a matrix of order $3 \times 2$. Therefore multiplication of these matrices is defined.

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