∣5AdjA∣=5
125∣adjA∣=5
Since [A] is 3×3
∣adjA∣=251
∣A∣2=251
∣A∣=±51.
JEE Main 2015 — Mathematics Algebra
If A is a 3×3 matrix such that ∣5adjA∣=5, then ∣A∣ is equal to
Held on 11 Apr 2015 · Verified 6 Jul 2026.
±251
±5
±51
±1
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