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AP EAMCET201822 Apr 2018Evening ShiftMathematicsVector AlgebraActual

If a , b , c are non-coplanar unit vectors such that a ( b c )= b + c 2 , then the angle between a and b is

Options

  1. A6
  2. B4
  3. C2
  4. D3 4

Correct answer

D. 3 4

Step-by-step solution

Since, a ( b c ) =( a c ) b -( a b ) c = b + c 2 (given) So, a b = -1 2 =- 1 2 a and b are unit vector where is angle between vectors a and b = 3 4 .

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