alleryFor a 3x3 matrix A: (A + Aᵀ) is always:
ASkew-symmetric
BSymmetric
CZero matrix
DDiagonal matrix
Answer & Solution
Correct answer: B. Symmetric
We have (A + Aᵀ)ᵀ = Aᵀ + A.
So (A + Aᵀ)ᵀ = A + Aᵀ.
Same as original, so symmetric.
Similarly (A - Aᵀ) is skew-symmetric.
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