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If the angle between the vector a and b is 3 , what is the angle between -5 a and 6 b ?

Options

  1. A6
  2. B2 3
  3. C2 5
  4. D3 7

Correct answer

B. 2 3

Step-by-step solution

aligned & = a b | a | b | & = .5 a 6 b .5 6 = - a b | a || b | & = ( - 3 )=2 / 3 . aligned

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