If A is a square matrix satisfying A′A=I, write the value of ∣A∣.Answer: ∣A∣=±1SolutionTake determinants of both sides and use ∣A′∣=∣A∣ and ∣AB∣=∣A∣∣B∣.∣A′A∣=∣I∣ ⇒ ∣A′∣∣A∣=1 ⇒ ∣A∣2=1 ⇒ ∣A∣=±1.∣A∣=±1CBSE Class 12 Board · 2019 · Subjective