If a matrix has 8 elements, what are possible orders it can have ?

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3 and 4 .Determinants and Matrices

easy

If a matrix has $8$ elements, what are the possible orders it can have ?

Option A

Option B

Option C

Option D

Solution

We know that if a matrix is of order $m \times n,$ it has $mn$ elements. Thus, to find all possible orders of a matrix with $8$ elements, we will find all ordered pairs of natural numbers, whose product is $8$ .

Thus, all possible ordered pairs are $(1,8),\,(8,1),\,(4,2),\,(2,4)$

Hence, possible orders are $1 \times 8$ , $8 \times 1$, $4 \times 2$ , $2 \times 4$

Standard 12

Mathematics

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hard

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normal

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