Matrices Lecture 4

If A and B matrices commute then

Seven different lecturers are to deliver lectures in seven perday. A, B and C are three oftne lectures. The number of ways in which a routine for theday canr be made such that A delivers his lecture before B and B before C, is

Which of the following matrices is equal to 4[(-1,2),(0,-4)] ?

If A and B are symmetric matrices, then ABA is

If A and P are the square matrices of the same order and if P be invertible, show that the matrices A and P^(-1) have the same characteristic roots.

If A and B are square matrices of order 3, then

Matrices of different order cannot be subtracted.

Expressing the following matrices as the sum of a symmetric and skew symmetric matrix : [[2,-2,-4],[-1,3,4],[1,-2,-3]]