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MHT CET202122 Sep 2021Evening ShiftMathematicsVector AlgebraActual

If the vectors 2 i - j - k ; i +2 j -3 k and 3 i + j +5 k are coplanar, then the value of is

Options

  1. A-8
  2. B-4
  3. C-2
  4. D-1

Correct answer

A. -8

Step-by-step solution

For given coplanar vectors, we write aligned & | array ccc 2 & -1 & -1 1 & 2 & -3 3 & & 5 array |= 2(10+3 )+(14)-( -6)=0 & 5 +40=0 =-8 aligned

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