Symmetric

If A is a square matrix then,
(A) A + A^T is symmetric (B) AAT is skew - symmetric (C) AT + A is skew-symmetric(D) A^TA is skew symmetric

2 Answers

correct ans A

(A + A^T)^T = A^T + (A^T)^T = A^T + A = A + A^T

(A^TA)^T=A^TA

So it is symmetric...

Same with AA^T...

Hence B and D are not true either.

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