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Manipal MET2018MathematicsVector Algebra

If | a + b |=| a - b | , then a and b are

Options

  1. Aparallel
  2. Bperpendicular
  3. Cangle between a and b is 45^
  4. Dangle between a and b is 60^

Correct answer

B. perpendicular

Step-by-step solution

Given, | a + b |=| a - b | array l | a + b |^2 =| a - b |^2 | a |^2+| b |^2+2 a b =| a |^2+| b |^2-2 a b 4 a b =0 array Hence, a is perpendicular to b .

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