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MHT CET20225 Aug 2022Evening ShiftMathematicsVector AlgebraActual

If angle between the vectors a =2 2 i +4 j + k and b =7 i -2 j + k i obtuse, then the values of lie in

Options

  1. A( 1 2 , )
  2. B[0, 1 2 ]
  3. C(0, 1 2 )
  4. D(- , 0)

Correct answer

C. (0, 1 2 )

Step-by-step solution

Angle between a and b is obtuse aligned & (2 2 i +4 j + k ) (7 i -2 j + k )<0 & 14 ^2-8 + <0 & 7 (2 -1)<0 & (0, 1 2 ) aligned

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