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BITSAT2022MathematicsMatricesActual

If [ array cc 1 & - & 1 array ] [ array cc 1 & - & 1 array ]⁻¹= [ array cc a & -b b & a array ], then

Options

  1. Aa=1, b=1
  2. Ba= 2 , b= 2
  3. Ca= 2 , b= 2
  4. DNone of these

Correct answer

C. a= 2 , b= 2

Step-by-step solution

Given, [ array cc 1 & - & 1 array ] [ array cc 1 & - & 1 array ]⁻¹= [ array cc a & -b b & a array ] [ array cc 1 & - & 1 array ] 1 1+ ^2 [ array cc 1 & - & 1 array ]= [ array cc a & -b b & a array ] 1 1+ ^2 [ array cc 1- ^2 & -2 2 & 1- ^2 array ]= [ array cc a & -b b & a array ] [ array cc 1- ^2 1+ ^2 & 2 1+ ^2 2 1+ ^2 & 1- ^2 1+ ^2 array ]= [ array cc a & -b b & a array ] [ array cc 2 & - 2 2 & 2 array ]= [ array cc a & -b b & a array ] a= 2 , b= 2

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