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MHT CET20227 Aug 2022Morning ShiftMathematicsVector AlgebraActual

If a and b are two vectors such that | a |=| b |= 2 with a b =-1 , then the angle between a and b is

Options

  1. A3 4
  2. B5 6
  3. C5 9
  4. D2 3

Correct answer

D. 2 3

Step-by-step solution

= ⁻¹ ( a b | a || b | )= ⁻¹ ( -1 2 2 )= ⁻¹ ( -1 2 )= 2 3

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