Observe that a scalar matrix is an identity matrix when k = 1 But every identity
matrix is clearly a scalar matrix Rationalised 2023-24
MATRICES         41
(vii)
Zero matrix
A matrix is said to be zero matrix or null matrix if all its elements are zero For example, [0], 
0
0
0
0





 , 
0
0
0
0
0
0





 , [0, 0] are all zero matrices