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MHT CET202120 Sep 2021Morning ShiftMathematicsMatricesActual

If inverse of [ array ccc 1 & 2 & x 4 & -1 & 7 2 & 4 & -6 array ] does not exist, then x=

Options

  1. A-3
  2. B2
  3. C3
  4. D0

Correct answer

A. -3

Step-by-step solution

aligned & Here [ array ccc 1 & 2 & x 4 & -1 & 7 2 & 4 & -6 array ]=0 & (6-28)-2(-24-14)+x(16+20)=0 & -22+76+18 x= x=-3 aligned

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