For what real value of is the matrix singular?

MATHEMATICS · Single correct · IB Diploma Programme · Mathematics: Applications and Interpretation · Number and Algebra · Number and Algebra

Problem

For what real value of

k

is the matrix

E=\begin{pmatrix}k &1 &2\\2 &k &1\\1 &2 &k\end{pmatrix}

singular? (a)

k=0

(b)

k=3

(c)

k=-3

(d)

k=\sqrt{3}