Define the scalar product of two vectors.

(N/A) The scalar product (or dot product) of two vectors $\vec{A}$ and $\vec{B}$ is defined as the product of the magnitudes of the two vectors and the cosine of the angle $\theta$ between them.
Mathematically,it is expressed as: $\vec{A} \cdot \vec{B} = AB \cos \theta$,where $A$ and $B$ are the magnitudes of vectors $\vec{A}$ and $\vec{B}$ respectively,and $\theta$ is the angle between them $(0 \le \theta \le \pi)$.
The result of the scalar product is a scalar quantity.