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NEST2020MathematicsVector Algebra

Let a , b and c be any three vectors. Then

Options

  1. Aa b + b c + c a =0 if a , b and c are unit vectors with a + b + c =0
  2. Ba + b , b + c and c + a are coplanar if a , b and c are coplanar
  3. C| a |=| b | if ( a + b ) ( a - b )=0
  4. Da = b if | a |=| b | and a b =0

Correct answer

C. | a |=| b | if ( a + b ) ( a - b )=0

Step-by-step solution

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