We have, A=⎣⎡649827531⎦⎤⇒A′=⎣⎡685423971⎦⎤ ∵A=(2A+A′)+(2A−A′)
Here, 2A+A′ is the symmetric part of A and 2A−A′ is the skew-symmetric part of A. ∴ We have, symmetric matrix, B=2A+A′ =21⎩⎨⎧⎣⎡649827531⎦⎤+⎣⎡685423971⎦⎤⎭⎬⎫ =21[1214410102]=[672551]