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JEE Main2002MathematicsVector AlgebraActual

If | a |=4,| b |=2 and the angle between a and b is / 6 then ( a b )^2=2 is equal to

Options

  1. A48
  2. B16
  3. Ca
  4. Dnone of these

Correct answer

B. 16

Step-by-step solution

We have, a b =| a || b | 6 =4 2 3 2 =4 3 Now, ( a b )^2+( a b )^2=a^2 b^2 ( a b )^2+48=16 4 ( a b )^2=16

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