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Consider an identity matrix (n n) I_n ; R⁺ then | Adj ( I_n ) | is

Options

  1. A^ n-1
  2. B^ n(n-1)
  3. C^n
  4. D^ 2(n-1)

Correct answer

B. ^ n(n-1)

Step-by-step solution

( I_n ) Adj ( I_n )= | I_n | I Adj ( I_n )= ^ n-1 I_n | Adj ( I_n ) |= ^ n(n-1)

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