If matrix A is skew-symmetric then,
 if 
 and 
 if 
 if 
 and 
 if 
 if 
 and 
 if 
 if 
 and 
 if 
                
                  
symmetric and skew symmetric matrix -
symmetric matrix: A square matrix  is said to be symmetric if A' = A,
    
    
Skew-symmetric matrix:  A square matrix   is said to be skew-symmetric if A’ = -A 
That means all the diagonal element of the skew-symmetric matrix is 0 but not the other way around.
-
In a skew-symmetric matrix diagonal element is zero
And 
Study 40% syllabus and score up to 100% marks in JEE