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Scalar product

The scalar product is an important link between the algebra of vectors and the trigonometry of vectors. We shall see that the scalar product is somewhat comparable to the operation of multiplication on real numbers.

What is the scalar (dot) product?

• The scalar product between two vectors a and b is represented by 

  • This is also called the dot product because of the symbol used

• The scalar product between two vectors  and  is defined as 

• The result of taking the scalar product of two vectors is a real number

  • i.e. a scalar

• For example,

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