Identity Matrix, symmetric Matrix, Idempotent Matrix , Null Matrix. #NTA #NetEconomics #JRF #IES

An identity matrix I is a square matrix which has 1 for every element on the principal diagonal from left to right and O everywhere else. I Video it is explained with an example The identity matrix is similar to the number 1 in algebra since multiplication of a matrix by an identity matrix leaves the original matrix unchanged (that is AI = IA = A). Multiplication of an identity matrix by itself leaves the identity matrix unchanged: SYMMETRIC MATRIX: Any matrix for which A = A' is a symmetric matrix. IDEMPOTENT MATRIX: A symmetric matrix for which AXA =A is an idempotent matrix. The identity matrix is symmetric and idempotent. NULL MATRIX: A null matrix is composed of all zeros and can be of any dimension; it is not necessarily square. Addition or subtraction of the null matrix leaves the original matrix unchanged; multiplication by a null matrix produces a null Matrix You can Join On Facebook https://www.facebook.com/profile.php?id=100028159118237 Facebook page https://www.facebook.com/ECONMATHSS/ On Telegram https://t.me/Hilal885