If A is a m × n matrix and B is a matrix such that both AB and BA are defined, then order of B is

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3 and 4 .Determinants and Matrices

easy

If $A$ is a $m \times n$matrix and $B$ is a matrix such that both $AB$ and $BA$ are defined, then the order of $B$ is

A

$m \times n$

B

$n \times m$

C

$m \times m$

D

$n \times n$

Solution

(b) It is obvious.

Standard 12

Mathematics

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