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Let a → = 2 i ^ - j ^ + 3 k ^ , b → = i ^ + j ^ - 4 k ^ and non-zero vector c → are such that a → × b → × c → = a → × b → × c → , then vector c → may be

Options

  1. A4 i ^ - 2 j ^ + 6 k ^
  2. B4 i ^ + 2 j ^ + 6 k ^
  3. Ci ^ + j ^ - k ^
  4. Di ^ - 4 j ^ + k ^

Correct answer

A. 4 i ^ - 2 j ^ + 6 k ^

Step-by-step solution

a → × b → × c → = a → × b → × c → a → ⋅ c → b → − b → ⋅ c → a → = a → ⋅ c → b → − a → ⋅ b → c → ⇒ c → must be parallel to a →

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