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MHT CET20228 Aug 2022Morning ShiftMathematicsVector AlgebraActual

The position vectors of vertices of A B C are 4 i -2 j ; i +4 j -3 k and - i +5 j + k respectively, then m A B C=

Options

  1. A3
  2. B4
  3. C6
  4. D2

Correct answer

D. 2

Step-by-step solution

aligned & A B C= angle between B A and B C & = ⁻¹ ( B A B C | B A || B C | )= ⁻¹ ( (3 i -6 j +3 k ) (-2 i + j +4 k ) 3^2+(-6)^2+3^2 (-2)^2+1^2+4^2 ) & = ⁻¹ ( 6-6+12 54 21 )= ⁻¹(0)= 2 aligned

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