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If a → = 2 i ^ + 3 j ^ + 4 k ^ , a → ⋅ b → = 2 and a → × b → = 2 i ^ - k ^ , then b → is

Options

  1. Ai ^ - 2 j ^ + k ^
  2. B4 i ^ - 4 j ^ + 2 k ^
  3. C1 2 3 i ^ + 7 j ^ + 9 k ^
  4. D1 29 7 i ^ - 4 j ^ + 14 k ^

Correct answer

D. 1 29 7 i ^ - 4 j ^ + 14 k ^

Step-by-step solution

a → × b → = 2 i ^ - k ^ a → × b → × a → = 2 i ^ - k ^ × 2 i ^ + 3 j ^ + 4 k ^ 29 b → - 2 a → = 3 i ^ - 10 j ^ + 6 k ^ b → = 1 29 7 i ^ - 4 j ^ + 14 k ^

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