alleryFor a 3x3 matrix A, A·(adj A) equals:
AA
BAᵀ
Cdet(A) × I
DI
Answer & Solution
Correct answer: C. det(A) × I
A·(adj A) = (adj A)·A = det(A) × I. This is how the inverse is constructed: A⁻¹ = adj(A)/det(A).
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