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BITSAT2019MathematicsVector AlgebraActual

If a → , b → , c → are non-coplaner vectors such that b → × c → = a → ; c → × a → = b → ; a → × b → = c → , then which of the following is not TRUE?

Options

  1. A| a → | - | b → | = 0
  2. B| a → | = | b → | = | c → | = 2
  3. Ca → b → c → = 1
  4. D| a → | | b → | | c → | = 1

Correct answer

B. | a → | = | b → | = | c → | = 2

Step-by-step solution

Given, a → × b → = c → b → × c → = a → c → × a → = b → ( b → × c → ) · a → = a → · a → ( c → × a → ) · b → = b → · b → a → 2 - b → 2 = ( b → × c → ) · a → - ( c → × a → ) · b → = [ c → a → b → ] - [ b → c → a → ] = 0 ∴   | a → | 2 - | b &#8

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