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JEE Main2006MathematicsVector AlgebraActual

If ( a b ) c = a ( b c ) , where a , b and c are any three vectors such that a b 0 , b c 0 , then a and c are

Options

  1. Ainclined at an angle of / 3 between them
  2. Binclined at an angle of / 6 between them
  3. Cperpendicular
  4. Dparallel

Correct answer

D. parallel

Step-by-step solution

( a b ) c = a ( b c ), a b 0, b c 0 ( a c ) b -( b c ) a =( a c ) b -( a b ) c ( a b ) c =( b c ) a a | c

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