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Evaluate (cos π/9 + i sin π/9 )18 = ?

  1. 0
  2. 1
  3. 1/2
  4. None of these

Answer (Detailed Solution Below)

Option 2 : 1
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Detailed Solution

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Concept:

Calculation:

As we know that, 

⇒ (cos π/9 + i sin π/9 )18 

= [ei ⋅ π/9]18 = ei ⋅ 2π

⇒ ei ⋅ 2π 

= cos 2π + i sin 2π = 1

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