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AP EAMCET2010MathematicsVector Algebra

If the angle between the vectors a =2 x^2 i +4 x j + k and b =7 i -2 j +x k is such that 90^ < < 180^ , then x lies in the interval

Options

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

Correct answer

A. (0, 1 2 )

Step-by-step solution

Given, a =2 x^2 i +4 x j + k b =7 i -2 j +x k , also 90^ So, x (0, 1 2 )

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