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KCET2010MathematicsMatrices

If A is a 3 3 non-singular matrix and if | A |=3 , then |(2 ~A )⁻¹ | is

Options

  1. A24
  2. B3
  3. C1 3
  4. D1 24

Correct answer

D. 1 24

Step-by-step solution

Given, |A|_ 3 3 0 and |A|=3 Then, aligned & |(2 ~A )⁻¹ |= | 1 2 ~A |= 1 |2 ~A | &= 1 (2)³ 1 | ~A | ( | aA |= a ³| ~A | ) &= 1 8 1 3 = 1 24 aligned

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