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COMEDK2020MathematicsVector Algebra

O A and B O are two vectors of magnitudes 5 and 6 respectively. If B O A=60^ , then OA O B is equal to

Options

  1. A15
  2. B0
  3. C15 3
  4. D-15

Correct answer

A. 15

Step-by-step solution

We have, aligned | OA |=5,| OB | &=6, BOA =60^ Now, OA OB &=| OA || OB | ( B O A) &=5 6 60^ =5 6 1 2 =15 aligned

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