If \(B=\left[ \begin{matrix}5 & 2\alpha & 1 \\0 & 2 & 1 \\\alpha & 3 & -1 \\\end{matrix} \right]\) is the inverse of a 3 × 3 matrix A, then the sum of all values of α for which det(A) + 1 = 0, is:

If \(B=\left[ \begin{matrix}5 & 2\alpha & 1 \\0 & 2 & 1 \\\alpha & 3 &

1.	If \(B=\left[ \begin{matrix}5 & 2\alpha & 1 \\0 & 2 & 1 \\\alpha & 3 & -1 \\\end{matrix} \right]\) is the inverse of a 3 × 3 matrix A, then the sum of all values of α for which det(A) + 1 = 0, is:
A.	0
B.	-1
C.	1
D.	2
Answer» D. 2