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# In the matrix $A=\begin{bmatrix}2 & 5 & 19 & -7\\35 & -2 & \frac{5}{2} & 12\\\sqrt 3 & 1 & -5& 17\end{bmatrix},$ write the elements $\;a_{13},a_{21},a_{33},a_{24},a_{23}$ 

$\begin{array}{1 1} a13 = 19 a21 = 35 a33 = -5 a24 = 17 a23= 5/2 \\a13 = 19 a21 = 5 a33 = -5 a24 = 12 a23= 5/2 \\a13 = 19 a21 = 35 a33 = -5 a24 = 12 a23= 5/2 \\ a13 = 12 a21 = 35 a33 = -5 a24 = 12 a23= 5/2\end{array}$

Options:0, 0, 0, 0, 019, 35, -5, 12, 5/22, 5, 19, -7, -519, 35, 5, 5/2, -12
Toolbox:
• Elements of matrix can be determined by looking at the value in the corresponding row and column. i.e, $a_{ij}$ is element lying in the i-th row and j-th column.
Let us compare the elements that correspond to a particular row and column:
• $a_{13}$→ 1st row and 3rd column = 19
• $a_{21}$→ 2nd row and 1st column = 35
• $a_{33}$→ 3rd row and 3rd column = -5
• $a_{24}$→ 2nd row and 4th column = 12
• $a_{23}$→ 2nd row and 3rd column = 5/2