## What is the dot product of two vectors graphically?

Algebraically, the dot 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. These definitions are equivalent when using Cartesian coordinates.

**What is the vector dot product used for?**

The dot product essentially tells us how much of the force vector is applied in the direction of the motion vector. The dot product can also help us measure the angle formed by a pair of vectors and the position of a vector relative to the coordinate axes.

**Does it make sense to take the dot product of more than two vectors?**

You cannot dot three vectors, only two. This is because when you dot two vectors you get a scalar. The dot product of two vectors divided by the magnitudes of the two vectors gives the cosine of the angle between the vectors.

### Is dot product of matrices commutative?

Matrix multiplication is not commutative in general.

**What does negative dot product mean?**

If the dot product is negative then the angle is greater than 90 degrees and one vector has a component in the opposite direction of the other. Thus the simple sign of the dot product gives information about the geometric relationship of the two vectors.

**Why do we need the dot product?**

Learn about the dot product and how it measures the relative direction of two vectors. The dot product is a fundamental way we can combine two vectors. Intuitively, it tells us something about how much two vectors point in the same direction.

## Can you multiply 3 vectors?

Suggested background. The scalar triple product of three vectors a, b, and c is (a×b)⋅c. It is a scalar product because, just like the dot product, it evaluates to a single number. (In this way, it is unlike the cross product, which is a vector.)