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If P= [ array lll 1 & & 3 1 & 3 & 3 2 & 4 & 4 array ] is the adjoint of a 3 3 matrix A and |A|=4 , then is equal to

Options

  1. A4
  2. B5
  3. C11
  4. D0

Correct answer

C. 11

Step-by-step solution

P= [ array lll 1 & & 3 1 & 3 & 3 2 & 4 & 4 array ] For 3 3 , matrix, | adj A|=|A|^2| adj A|=(4)^2=16 Now, P= | array lll 1 & & 3 1 & 3 & 3 2 & 4 & 4 array |=16 1(12-12)- (4-6)+3(4-6)=16 0+2 -6=16 2 =22 Hence, =11

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