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title: Dot Product
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# Dot Product
The dot product of vectors is also know as the “scalar” product.
#### Formula
If a and b are two vectors meeting at a point, whose moduli are |a| and |b| respectively and θ is the angle between them, then the “dot” or “scalar” product of the two vectors is given as:
a.b = |a||a| cosθ
Also, if the two vectors (a and b) are given in terms of their [unit vectors](https://en.wikipedia.org/wiki/Unit_vector), where
a = x1i + y1j
and
b = x2i + y2j
Their dot product is given as:
a.b = (x1i + y1j) * (x2i + y2j)
Since i and j are [unit vectors](https://en.wikipedia.org/wiki/Unit_vector) (equivalent to one), then
a.b = (x1 * x2) + (y1 * y2)
### More Information:
1. [Euclidean vector](https://en.wikipedia.org/wiki/Euclidean_vector)
2. [Vector and Vector Arithmetic](http://spiff.rit.edu/classes/phys311.old/lectures/vector/vector.html)