A square matrix A = [{a_{ij}}] in which {a_{ij}} = 0 for i, ne j and {a_{ij}} = k (constant) for i =

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3 and 4 .Determinants and Matrices

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A square matrix $A = [{a_{ij}}]$ in which ${a_{ij}} = 0$ for $i\, \ne j$ and ${a_{ij}} = k$ (constant) for $i = j$ is called a

A

Unit matrix

B

Scalar matrix

C

Null matrix

D

Diagonal matrix

Solution

(b)When ${a_{ij}} = 0$ for $i \ne j$ and ${a_{ij}}$ is constant for $i = j,$ then the matrix ${[{a_{ij}}]_{n \times n}}$ is called a scalar matrix.

Standard 12

Mathematics

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