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For what value of the angle between the vectors  is the quantity  maximum? 

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NDA-II 2024 (Maths) Official Paper (Held On: 01 Sept, 2024)
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  1. 0°
  2. 30°
  3. 45°
  4. 60°

Answer (Detailed Solution Below)

Option 2 : 30°
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Detailed Solution

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Explanation:

Let P = 

= 

= 

⇒ p will be max if (sin 3 + √ 3cos θ) is maximum.

Now, for its maxima,

⇒ Cosθ -√3 sinθ =0

⇒ 

⇒ θ =30°

∴ Option (b) is correct

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