Maths-
General
Easy
Question
A square matrix 
for 
and 
(constant) for 
is called a
- unit matrix
- scalar matrix
- Null matrix
- Diagonal matrix
Hint:
Matrix of size n in n 
n square matrix with1 on the main diagonal and zero elsewhere is Unit matrix. A diagonal matrix is a matrix having non-zero elements only in the diagonal running from the upper left to the lower right. A scalar matrix is the special case diagonal matrix with all the diagonals elements equal and all off-diagonals element not equal. Null matrix is the matrix with all the elements zero.
The correct answer is: scalar matrix
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