Matrices definitions

Null matrix

Identity matrix

Transpose of a matrix

When the rows and columns are swapped

(AB)^T

=B^T A^T

No inverse

Determine = 0

Singular

Determine = 0

Non singular

Determine doesn’t = 0

P and Q are non singular matrices. Prove that (PQ)^-1= Q^-1 P^-1

Let X =(PQ)^-1

If asked to prove a matrix is self inverse..

You must prove that A=A^-1