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JEE Main2015MathematicsVector AlgebraActual

Let a → , b → and c → be three non - zero vectors such that no two of them are collinear and a → × b → × c → = 1 3 b → c → a → . If θ is the angle between vectors b → and c → , then a value of sin θ is

Options

  1. A- 2 3 3
  2. B2 2 3
  3. C- 2 3
  4. D2 3

Correct answer

B. 2 2 3

Step-by-step solution

Given a →   ×   b →   ×   c → =   1 3   b →   c → a → a → ⋅ c →   b → -   b → ⋅ c →   a → = 1 3   b → c →   a → ⇒   a → ⋅ c → = 0     and   b → ⋅ c → =   - 1 3   b → c → b → c → cos θ =   - 1 3   b → c → cos θ = &#1

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