1.

Show that a matrix which is both symmetric and skew symmetric is a zero matrix.

Answer»

Let A = [aij] be a matrix which is both symmetric and skew symmetric.

Since A is a skew symmetric matrix, so A′ = –A.

Thus for all i and j, we have aij = – aji. .........(1)

Again, since A is a symmetric matrix, so A′ = A.

Thus, for all i and j, we have

aji = aij .............(2)

Therefore, from (1) and (2), we get

aij = –aij for all i and j

or 2aij = 0,

i.e., aij = 0 for all i and j. Hence A is a zero matrix.



Discussion

No Comment Found

Related InterviewSolutions