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If a → = i ^ + j ^ + 2 k ^ , b → = i ^ + 2 j ^ + 2 k ^ and c → = 1 , then the maximum value of a → × b →     b → × c →     c → × a → is equal to

Options

  1. A2
  2. B3
  3. C4
  4. D5

Correct answer

D. 5

Step-by-step solution

a → × b →   b → × c →   c → × a → = a →   b →   c → 2 = a → × b → . c → 2 a → × b → . c → is maximum, if a → × b → is parallel to c → Hence, the maximum value = a → × b → 2 c → 2 = 5

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