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KCET2023MathematicsVector Algebra

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

Options

  1. Aa and b are parallel.
  2. Ba and b are coincident.
  3. Cinclined to each other at 60^ .
  4. Da and b are perpendicular.

Correct answer

D. a and b are perpendicular.

Step-by-step solution

Let a and b be two vectors | a + b |=| a - b | On squaring on both sides, we get a^2+b^2+2 a b =a^2+b^2-2 a b 4 a b =0 If a=0, b=0 , then =0 = ( 2 n-1 2 ) , where n N Hence, a and b are perpendicular.

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