For which kkk is the matrix A=(k23k−1)A = \begin{pmatrix} k & 2 \\ 3 & k-1 \end{pmatrix}A=(k32k−1) singular?
k=3k = 3k=3 or k=−2k = -2k=−2
k=−3k = -3k=−3 or k=2k = 2k=2
k=1k = 1k=1 or k=0k = 0k=0
k=3k = 3k=3 or k=2k = 2k=2