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MHT CET2008MathematicsVector Algebra

If the vectors i -3 j +2 k ,- i +2 j represents the diagonals of a parallelogram, then its area will be

Options

  1. A21
  2. B21 2
  3. C2 21
  4. D21 4

Correct answer

B. 21 2

Step-by-step solution

Let a = i -3 j +2 k , b =- i +2 j Now, a b = | array rrr i & j & k 1 & -3 & 2 -1 & 2 & 0 array |=-4 i -2 j - k Hence, required area = 1 2 | a b |= 1 2 16+4+1 = 21 2

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