Question

If the matrix $A=\left[\begin{array}{ccc}8& -6& 2\\ -6& 7& -4\\ 2& -4& \lambda \end{array}\right]$ is singular, then $\lambda =$

• A. 5
• B. 4
• C. 3
• D. 2

Answer 1

Answer: (C)

$|A|=0\Rightarrow 20\lambda -60=0\Rightarrow \lambda =3$