If $A$ and $B$ are two matrices of order $4 \times m$ and $4 \times n$, respectively and $m=n$ then the order of matrix $(5 A-2 B)$ is :
Answer & explanation
Correct answer: option 1
The correct answer is Option 1: $4 \times m$
A is of order 4 × m
B is of order 4 × n
We are told m = n
So, both matrices A and B have the same order: 4 × m (or equivalently, 4 × n)
Now for the operation:
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5A − 2B is valid only if A and B are of the same order — which they are: 4 × m
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Scalar multiplication does not change the order
Therefore, the order of (5A − 2B) is : 4 × m