MCQ
If $A^3=O$, then $A^2+A+I=$
  • A
    $I-A$
  • $(I-A)^{-1}$
  • C
    $(I+A)^{-1}$
  • D
    $I+A$

Answer

Correct option: B.
$(I-A)^{-1}$
(b) $: I-A^3=I \Rightarrow(I-A)\left(I+A+A^2\right)=I$
$\therefore \quad I+A+A^2=(I-A)^{-1}$.

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