Vectors in a plane
The scalar product or dot product of two vectors is a way to multiply two vectors together. The result you’ll get is a number, not a new vector. You can’t get a new vector when multiplying two vectors.
The scalar product is written with a bold dot (hence the word “dot product”). It’s given by:
The scalar product is among other thing used to determine angles between two vectors.
Two vectors are perpendicular if the scalar product is 0.