The angle between two vectors

 and  is- (Given, Cos^-1() = 89°)

CONCEPT:

The dot product of two vectors

• The dot product or scalar 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.
• Let the two vectors are A and B then dot Product of two vectors:

⇒  A⋅B = |A||B| cos θ 

Where |A| = Magnitude of vectors A and |B| = Magnitude of vectors B and θ is the angle between A and B.

The above equation can be rewritten as:

• The dot product of unit vectors

​CALCULATION:

Given- The two vectors are  and .

• The dot product of given vectors:

• The magnitude of vector A:

• The magnitude of vector B:

• The angle between vectors A and B:

Therefore, option 4 is correct.

Important Points

• Cross product of unit vectors

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