Question

The value of determinant using Bagula rule $\left|\begin{array}{ccc}4& -2& 1\\ 9& 2& -3\\ 2& 1& 0\end{array}\right|$ is

• A. $2$
• B. $29$
• C. $38$
• D. $55$

Answer 1

The correct option is B $29$

Using 'Bagula' method : $\left|\begin{array}{ccc}{a}_1& b_1& c_1\\ a_2& b_2& c_2\\ a_3& b_3& c_3\end{array}\right|=[a_1{b}_2{c}_3+b_1{c}_2{a}_3+c_1{a}_2{b}_3]-[a_3{b}_2{c}_1+b_3{c}_2{a}_1+c_3{a}_2{b}_1]$
$\left(\right[$sum of product of elements in principal diagonal and elements forming its 'star'] - [sum of product of elements in geometrical diagonal and elements forming its 'star'$\left]\right)$
$=[0+12+9]-[4+0-12]=29$