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AP EAMCET2006MathematicsVector Algebra

If i -3 j + k and i +3 j are coplanar, then is equal to :

Options

  1. A-1
  2. B1 / 2
  3. C-3 / 2
  4. D2

Correct answer

C. -3 / 2

Step-by-step solution

Since i -2 j , 3 j + k and i +3 j are coplanar, then | array ccc 1 & -2 & 0 0 & 3 & 1 & 3 & 0 array |=0 1 | array ll 3 & 1 3 & 0 array |+2 | array ll 0 & 1 & 0 array |=0 -3+2(- )=0 =- 3 2

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