The value of k, for which is A = \(\begin{bmatrix}k & 12 \\3 & 3k \end{bmatrix}\) singular matrix is
Answer & explanation
Correct answer: option 3
Finding the determinant and equating it to 0.
\(3 { k }^{ 2 } - 36 = 0\)
\(3 ({ k }^{ 2 } - 12) = 0\)
\({ k }^{ 2 } - 12= 0\)
\({ k }^{ 2 } = 12\)
k = \(2\sqrt { 3 }\), \(-2\sqrt { 3 }\)