symmetric matrix:A(ij)=A(ji),or AT = A skew symmetric:A(ij)= -A(ji),or AT = -A Here,A(ij) is the element in ith row and jth column of matrix A. AT is the transpose of matrix A. e.g.A= [1 2 3] [2 9 4] [3 4 5] is symmetric. A=[1 2 3] [-2 9 -4] [-3 4 5] is skew-symmetric.