If A is a square matrix such that A^2 = I, then A^ -1 is equal to… - Vidyadip

MCQ

If $A$ is a square matrix such that $A^2 = I,$ then $A^{-1}$ is equal to:

A
$A + I$
✓
$A$
C
$0$
D
$2A$

✓

Answer

Correct option: B.

$A$

$A^2 = I$
$A^{-1}A^2 = A^{-1}I$
$A = A^{-1}$

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