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MHT CET202016 Oct 2020Evening ShiftMathematicsMatricesActual

The matrix A= [ array ccc a & -1 & 4 -3 & 0 & 1 -1 & 1 & 2 array ] is not invertible only if a =

Options

  1. A-17
  2. B-16
  3. C16
  4. D17

Correct answer

A. -17

Step-by-step solution

(D) Since A is not invertible, | A |=0 aligned & | array ccc a & -1 & 4 -3 & 0 & 1 -1 & 1 & 2 array |=0 & a (0-1)-(-1)(-6+1)+4(-3-0)=0 - a -5-12=0 a =-17 aligned

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