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KCET2016MathematicsVector Algebra

If ( 2 a b =| a | | b | ) then the angle between ( a & b ) is

Options

  1. A( 30^ )
  2. B( 0^ )
  3. C( 90^ )
  4. D( 60^ )

Correct answer

D. ( 60^ )

Step-by-step solution

Given that, ( 2 a b =| a | | b | ) As we know, ( a b =| a || b | ) So, ( 2| a || b | =| a || b | ) ( 2 =1 ) ( = 1 2 =60^ )

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