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If A is a square matrix of order n such that | adj ( adj A)|=|A|^9 , then the value of n can be

Options

  1. A4
  2. B2
  3. Ceither 4 or 2
  4. DNone of these

Correct answer

A. 4

Step-by-step solution

We know that, in a square matrix of order n| adj A|=|A|^ n-1 aligned & | adj ( adj A)|=| adj A|^ n-1 =|A|^ (n-1)^2 & n^2-2 n-8=0 & n=4 as n=-2 is not possible. aligned

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