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Let a → + b → + c → = 0 → , where a → , b → and c → are three non-zero vectors such that the angle between a → and b → is π 3 . If the angle between b → and c → is π 18 , then the angle between a → and c → is

Options

  1. A5 π 18
  2. B11 π 18
  3. Cπ 2
  4. Dπ 6

Correct answer

A. 5 π 18

Step-by-step solution

From the figure, it is clear that a → ,   b → ,   c → forms a triangle ∴ Angle between a →   &   c → = π - 2 π 3 - π 18 = 5 π 18

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