Question

In the matrix
$A=\left[\begin{array}{cccc}2& 5& 19& -7\\ 35& -2& \frac{5}{2}& 12\\ \sqrt{3}& 1& -5& 17\end{array}\right]$

$\left(i\right).$ Write the order of the matrix
$\left(ii\right).$ Write the numbers of element.
$\left(iii\right).$ Write the elements $a_{13},a_{21},a_{33},a_{24},a_{23}$

Answer 1

$\left(i\right)$ Given : $A=\left[\begin{array}{cccc}2& 5& 19& -7\\ 35& -2& \frac{5}{2}& 12\\ \sqrt{3}& 1& -5& 17\end{array}\right]$
Since the matrix has
$3\text{row}\text{and}4\text{columns}$
$\therefore$ Order of matrix $A=3\times 4$


$\left(ii\right)$ Given : $A=\left[\begin{array}{cccc}2& 5& 19& -7\\ 35& -2& \frac{5}{2}& 12\\ \sqrt{3}& 1& -5& 17\end{array}\right]$
The order of matrix is $3\times 4$
So, number of elements $=3\times 4=12$


$\left(iii\right)$ Given : $A=\left[\begin{array}{cccc}2& 5& 19& -7\\ 35& -2& \frac{5}{2}& 12\\ \sqrt{3}& 1& -5& 17\end{array}\right]$
$a_{ij}$ represents element of $i^{th}$ row and $j^{th}$ column.
$\therefore a_{13}=19$,
$a_{21}=35$,
$a_{33}=-5$,
$a_{24}=12$,
$a_{23}=\frac{5}{2}$