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If the matrix A= [ array ll & & array ] is such that A^2=1 , then which one of the following is correct?

Options

  1. A=0, =1 or =1, =0
  2. B=0, 1 or 0, =1
  3. C=1, 0 or 1, =0
  4. D0, 0

Correct answer

A. =0, =1 or =1, =0

Step-by-step solution

A= [ array ll - & - & array ] A^2= [ array ll & & array ] [ array ll & & array ] A^2= [ array cc ^2+ ^2 & 2 2 & ^2+ ^2 array ] Given that A ^2=1 aligned & [ array cc ^2+ ^2 & 2 2 & ^2+ ^2 array ]= [ array ll 1 & 0 0 & 1 array ] & ^2+ ^2=1 and =0 & =0, =1 or =1, =0 . aligned

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