Question

If $A=\left[\begin{array}{cc}1-2& 3\end{array}\right],B=\left[\begin{array}{c}2\\ -3\\ -1\end{array}\right]$, then $AB$ is equal to

• A. $\left[\begin{array}{c}2\\ -3\\ -1\end{array}\right]$
• B. $\left[\begin{array}{c}r2\\ 6\\ -3\end{array}\right]$
• C. $[26-3]$
• D. none of these

Answer 1

Answer: (D)

$AB=\left[\begin{array}{ccc}1& -2& 3\end{array}\right]\left[\begin{array}{c}2\\ -3\\ -1\end{array}\right]=[2+6-3]=[5]$