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AP EAMCET202119 Aug 2021Morning ShiftMathematicsVector AlgebraActual

If a → = 2 i ^ + j ^ + 3 k ^ , b → = i ^ + 3 j ^ - k ^ and c → = 3 i ^ - j ^ - 2 k ^ then, the value of a → · a → a → · b → a → · c → b → · a → b → · b → b → · c → c → · a → c → · b → c → · c → is

Options

  1. A2020
  2. B2025
  3. C2030
  4. D1849

Correct answer

B. 2025

Step-by-step solution

Given that, If a → = 2 i ^ + j ^ + 3 k ^ , b → = i ^ + 3 j ^ - k ^ and c → = 3 i ^ - j ^ - 2 k ^ ⇒ a → · a → = 14 ,   b → · b → = 11 ,   c → · c → = 14 and a → · b → = b → · a → = 2 ,   a → · c → = c → · a → = - 1 ,   b → · c → = c → · b → = 2 Putting these values in a → · a → a → · b → a

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