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MHT CET202012 Oct 2020Evening ShiftMathematicsMatricesActual

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

Options

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

Correct answer

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

Step-by-step solution

We have A= [ array cc & - - & - array ] adj A= [ array cc - & & array ]|A|= | array cc & - - & - array |=- ² - ² =- ( ² + ² )=-1 A⁻¹= 1 (-1) [ array cc - & & array ]= [ array cc & - - & - array ]

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