Question

If $A=[a_{ij}{]}_{2\times 2}$, where $a_{ij}=i+j$ , then $A$ is equal to :

• A. $\left[\begin{array}{cc}1& 1\\ 2& 2\end{array}\right]$
• B. $\left[\begin{array}{cc}1& 2\\ 1& 2\end{array}\right]$
• C. $\left[\begin{array}{cc}1& 2\\ 3& 4\end{array}\right]$
• D. $\left[\begin{array}{cc}2& 3\\ 3& 4\end{array}\right]$

Answer 1

Answer: (D)

$\left[\begin{array}{cc}2& 3\\ 3& 4\end{array}\right]$

$A=\left[\begin{array}{cc}{a}_{11}& a_{12}\\ a_{21}& a_{22}\end{array}\right]$

$=\left[\begin{array}{cc}1+1& 1+2\\ 2+1& 2+2\end{array}\right]$

$=\left[\begin{array}{cc}2& 3\\ 3& 4\end{array}\right]$