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KCET2021MathematicsMatrices

If A and B are matrices of order 3 and |A|=5,|B|=3 , then |3 A B| is

Options

  1. A425
  2. B405
  3. C565
  4. D585

Correct answer

B. 405

Step-by-step solution

Given order of matrix A and B are 3 , |A|=5,|B|=3 The order of A B matrix is also 3 . |A B|=|A| |B|=15 Using the property |K A|=K^ n |A| , where n is the order of square matrix aligned |3 A B| &=3³|A B| &=27 15=405 aligned

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