If |A| denotes value of determinant of square matrix A of order 3 , then |-2A|=

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3 and 4 .Determinants and Matrices

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If $|A|$ denotes the value of the determinant of the square matrix $A$ of order $3$ , then $ |-2A|=$

A

$ - 8|A|$

B

$8|A|$

C

$ - 2|A|$

D

None of these

Solution

(a) If $A$ is square matrix of order $ 3$, then
$| – 2A| = {( – 2)^3}|A|\, = – 8|A|$.

Standard 12

Mathematics

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