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If | a + b |=| a - b | , then which one of the following is correct?

Options

  1. Aa = b for some scalar
  2. Ba is parallel to b
  3. Ca is perpendicular to b
  4. Da = b = 0

Correct answer

C. a is perpendicular to b

Step-by-step solution

If | a + b |=| a - b | We know that when ( a + b ) ( a - b )=0 , then a is perpendicular to b . = a a - a b + b a - b b =0 a is perpendicular to b Option (C) is correct.

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