Matrices A and B satisfy AB=B−1, where B=[2−120]. Then the value of the scalar k for which kA−2B−1+I=O is

Matrices A and B satisfy AB=B−1, where B=[2−120]. Then the value o

1.	Matrices A and B satisfy AB=B−1, where B=[2−120]. Then the value of the scalar k for which kA−2B−1+I=O is
Answer» Matrices $A$ and $B$ satisfy $A B = B^{- 1}$ , where $B = [\begin{matrix} 2 & - 1 2 & 0 \end{matrix}] .$ Then the value of the scalar $k$ for which $k A - 2 B^{- 1} + I = O$ is