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If the angle between  and the projection of  in the direction of  is -2, then 

  1. 4
  2. 3
  3. 2
  4. 1

Answer (Detailed Solution Below)

Option 1 : 4
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Detailed Solution

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Concept:

projection of  in the direction of    = 

Calculations:

Given, the angle between  and the projection of  in the direction of  is -2

We know that, 

projection of  in the direction of = 

⇒ - 2 = 

⇒ - 2 = 

⇒ - 2 = 

⇒  

Hence, if the angle between  and the projection of  in the direction of  is -2, then  4

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