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KCET2019MathematicsVector Algebra

If the angle between ( a ) and ( b ) is ( 2 3 ) and the projection of ( a ) in the direction of ( b ) is ( -2 ), then ( ) a ( 1= )

Options

  1. A( 03 )
  2. B( 11 )
  3. C( 04 )
  4. D( 12 )

Correct answer

C. ( 04 )

Step-by-step solution

(C) [ array l = 2 3 a b | b | =-2 | a || b | | b | =-2 | a | 2 3 =-2 | a | - 1 2 =-2 | a |=4 array ]

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