Question

If $\begin{vmatrix}0&3&2b\\ 2&0&1\\ 4&-1&6\end{vmatrix}$ is singular, then the value of $b$ is equal to

• A. - 3
• B. 3
• C. - 6
• D. 6
• E. - 2

Answer 1

Answer: (C)

A matrix whose determinant value is zero, is known as singular matrix.
Hence, $\begin{vmatrix}0 & 3 & 2 b \\ 2 & 0 & 1 \\ 4 & -1 & 6\end{vmatrix}=0$
Expanding along
$R_{1}$, we get $0(0+1)-3(12-4)+2 b(-2-0)=0$
$\Rightarrow -24-4 b=0$
$\therefore $ $b=-6$