We know that ∣adjA∣=∣A∣n−1
∣KA∣=Kn∣A∣
where n is order of matrix
Given
∣adj(24A)∣=∣adj3(adj2A)∣
⇒∣24A∣2=∣3adj(2A)∣2
⇒∣24A∣=∣3adj(2A)∣
⇒243∣A∣=33∣adj2A∣ ⇒243∣A∣=33∣2A∣∣2A∣
⇒243∣A∣=332323∣A∣∣A∣
⇒∣A∣=232333243 =2633(23⋅3)3 =8
⇒∣A∣2=64
JEE Main 2022 — Mathematics Algebra
Let A be a 3×3 invertible matrix. If ∣adj(24A)∣=adj(3adj(2A))∣, then ∣A∣2 is equal to
Held on 26 Jun 2022 · Verified 6 Jul 2026.
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