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Consider the following in respect of a non-singular matrix of order 3 : 1. A ( adj A )=( adj A ) A 2. | adj A |=| A | Which of the above statements is/are correct?

Options

  1. A1 only
  2. B2 only
  3. CBoth 1 and 2
  4. DNeither 1 nor 2

Correct answer

A. 1 only

Step-by-step solution

(1) We know that, A ( adj A)=( adj A) A=|A| I Hence, statement ( 1 ) is correct. (2) | adj (A)|= |A⁻¹ | A Hence, statement (2) is not correct.

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