Skew-symmetric 3x3 matrix found from its products with given vectors; determinant of an adjoint of 2(A + I) as powers of primes
The same question, asked 2 times: 24 Jan 2025*, 22 Jan 2026 S1. Every wording below, oldest first.
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Question 1
24 Jan 2025
74
Let be a 3×3 matrix such that XTAX=O for all nonzero 3×1 matrices X=xyz. If A111=14−5,A121=04−8, and det(adj(2(A+I)))=2α3β5γ,α,β,γ,∈N, then α2+β2+γ2 is
Question 2
22 Jan 2026 S1
72
Let A be a 3×3 matrix such that A+AT=O. If A1−10=332,A21−10=−319−24 and det(adj(2adj(A+I)))=(2)α⋅(3)β⋅(11)γ,α,β,γ are non-negative integers, then α+β+γ is equal to ____