Q. If $A^{2} - A + 1 = 0$, then the inverse of $A$ is
A) $A^{- 2}$
B) $A + I$
C) $I - A$
D) $A - I$
Explanation
(c)
$A^{2} - A + I = 0$
$\Rightarrow I = A - A^{2}$
$IA^{- 1} = AA^{- 1} - A^{2}A^{- 1}$
$\Rightarrow A^{- 1} = I - A$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.