If A is a square matrix then A−¯¯¯¯¯¯¯AT is a skew hermitian matrix.
True
Lets take general element from matrix A and verify if A−¯¯¯¯¯¯¯AT is a skew symmetric matrix.
Assume
aij = p + iq
aji = r + is
The expression A−¯¯¯¯¯¯¯AT will translate to aij =−¯¯¯¯¯¯¯aji at the elementary level in the resultant matrix.
If mij is the ijth element in resultant matrix
mij = aij−¯¯¯¯¯¯¯aij=(p+iq)−(r−is)
=(p – r)+ i (q + s) ….(1)
mji = aij−¯¯¯¯¯¯¯aij=(r+is)−(p−iq)
= r – p + I (q+s) ….(2)
From (1) & (2) we can see that
mij=−¯¯¯¯¯¯¯¯¯mji
Thisimplies that the resultant matrix or A−¯¯¯¯¯¯¯AT is skew hermitian.