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If A= ( array cc -2 & 2 2 & -2 array ) , then which one of the following is correct?

Options

  1. AA ^2=-2 ~A
  2. BA ^2=-4 ~A
  3. CA ^2=-3 ~A
  4. DA ^2=4 ~A

Correct answer

B. A ^2=-4 ~A

Step-by-step solution

aligned & A= ( array cc -2 & 2 2 & -2 array ) & A^2= ( array cc -2 & 2 2 & -2 array ) ( array cc -2 & 2 2 & -2 array ) aligned aligned & = ( array cc 4+4 & -4-4 -4-4 & 4+4 array )= ( array cc 8 & -8 -8 & 8 array ) & =-4 ( array cc -2 & 2 2 & -2 array )=-4 ~A aligned

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