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Question
A matrix A of order 3 × 3 is such that |A| = 4. Find the value of |2 A|.
Solution
\[\left| KA \right| = K^n \left| A \right| \]
Here, n is the order of A .
\[\text{ Given: }\left| A \right| = 4\]
\[ \Rightarrow \left| 2A \right| = 2^3 \times 4 = 32\]
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