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The angle between two vectors  and  given by-

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Answer (Detailed Solution Below)

Option 4 :
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CONCEPT:

The dot product of vector:

  • The dot product is the sum of the products of the corresponding entries of the two sequences of numbers.
  • Geometrically, it is the product of the Euclidean magnitudes of the two vectors and the cosine of the angle between them.

Where  are the magnitudes of two vectors A1 and A2

EXPLANATION:

  • The angle between two vectors  and  given by

  • Therefore option 4 is correct.

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