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Inverse of the matrix [ array cc 2 & - 2 2 & 2 array ] is

Options

  1. A[ array cc 2 & - 2 2 & 2 array ]
  2. B[ array cc 2 & 2 2 & - 2 array ]
  3. C[ array ll 2 & 2 2 & 2 array ]
  4. D[ array cc 2 & 2 - 2 & 2 array ]

Correct answer

D. [ array cc 2 & 2 - 2 & 2 array ]

Step-by-step solution

Let A= [ array cc 2 & - 2 2 & 2 array ] Now, |A|= | array cc 2 & - 2 2 & 2 array |= ² 2 - (- ² 2 )= ² 2 + ² 2 =1 Again, A⁻¹= 1 |A| | array cc 2 & 2 - 2 & 2 array | . [ array ll a & b c & d array ]⁻¹= 1 a d-b c [ array cc d & -b -c & a array ] ]= [ array cc 2 & 2 - 2 & 2 array ]

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