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MHT CET202411 May 2024Evening 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. A3 4
  2. B4
  3. C2

Correct answer

A. 3 4

Step-by-step solution

aligned & a ( b c )= b + c 2 & ( a c ) b -( a b ) c = b + c 2 & ( a c - 1 2 ) b - ( a b + 1 2 ) c =0 aligned Since a , b , c are non-coplanar unit vectors, aligned & a ~b + 1 2 =0 & a ~b =- 1 2 & | a || b | =- 1 2 & =- 1 2 & = 3 4 aligned

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