Eigen values of a real symmetric matrix are always
A.  positive 
B.  real and imaginary 
C.  negative 
D.  real 
Option: D Explanation : Click on Discuss to view users comments. 
If AT = A1, where A is a real matrix, then A is
A.  normal 
B.  symmetric 
C.  Hermitian 
D.  orthogonal 
Option: D Explanation : Click on Discuss to view users comments. 
If A and B are nonzero square matrices, then AB = 0 implies
A.  A and B are orthogonal 
B.  A and B are singular 
C.  B is singular 
D.  A is singular 
Option: A Explanation : Click on Discuss to view users comments. MABUD ALI SARKAR said: (1:39pm on Thursday 10th December 2015)
SINCE PRODUCT OF TWO NONZERO VECTORS IMPLIES THEY ARE ORTHOGONAL TO EACH OTHER. SO A and B ARE ORTHOGONAL

If A and B be real symmetric matrices of sizen n x n, then
A.  AA^{T} = 1 
B.  A = A^{1} 
C.  AB = BA 
D.  (AB)^{T} = BA 
Option: D Explanation : Click on Discuss to view users comments. MABUD ALI SARKAR said: (1:42pm on Thursday 10th December 2015)
(AB)^T=(B^T)(A^T) =BA
Zakir ali said: (8:30pm on Sunday 30th April 2017)
Please tell me about different type of matrices with example
