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JEE Main202122 Jul 2021Morning ShiftPhysicsMathematics in PhysicsActual

What will be the projection of vector A → = i ^ + j ^ + k ^ on vector B → = i ^ + j ^ ?

Options

  1. A2 ( i ^ + j ^ + k ^ )
  2. B2 i ^ + j ^ + k ^
  3. C2 ( i ^ + j ^ )
  4. D( i ^ + j ^ )

Correct answer

D. ( i ^ + j ^ )

Step-by-step solution

A cos θ B ^ = A A → · B → A B B ^ = A → · B → B B ^ = 2 2 i ^ + j ^ 2 = i ^ + j ^

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