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If A is semy square matrix of order 3 and det A=5 , then what is det [(2 ~A )⁻¹ ] equal to?

Options

  1. A1 / 10
  2. B2 / 5
  3. C8 / 5
  4. D1 / 40

Correct answer

D. 1 / 40

Step-by-step solution

aligned & |A|=5 |2 A|=2^3 5=40 & |A⁻¹ |= 1 |A| |(2 A)⁻¹ |= 1 |2 A| = 1 40 aligned

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