For a 3x3 matrix A: (A + Aᵀ) is always:
- Skew-symmetric
- Symmetric
- Zero matrix
- Diagonal matrix
Show answer and 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.