Vector geometry - is directed segment, which is characterized by an ordered pair of points in Euclidean space.
The length of a vector is the number that is equal to the length of the segment forming vector.
We find the square of the length of the vector. It is equal to the sum of the squares of its origin. That is to be squared each coordinate and the results add up.
Let us find the right length of the vector. It is equal to the square root of the sum of the vector coordinates. Again, the resulting number will be the source of the vector length.