Vectors

Vector length
l = saknis(x^2+y^2)

Spatial vector length
l = saknis(x^2 + y^2 + z^2)

Scalar (dot) product of vectors
A*B = a*b*cos(α)

Scalar (dot) product of vectors according to the coordinates
A*B = x1*x2 + y1*y2

Scalar (dot) product of spacial vectors according to the coordinates
A*B = x1*x2 + y1*y2 + z1*z2

Scalar (dot) product of vertical vectors
x1*x2 + y1*y2 = 0

Scalar (dot) product of spatial vertical vectors
x1*x2 + y1*y2 + z1*z2= 0

The angle between the vectors
cos(α) = (x1*x2 + y1*y2) / (saknis(x1^2 + y1^2) * saknis(x2^2 + y2^2))

The angle between the spacial vectors
cos(α) = (x1*x2 + y1*y2 + z1*z2) / (saknis(x1^2 + y1^2 + z1^2) * saknis(x2^2 + y2^2 + z2^2))

Collinear vectors
x1 / x2 = y1 / y2

The distance between points
AB = saknis((x2 - x1)^2 + (y2 - y1)^2)

The distance between points in space
AB = saknis((x2 - x1)^2 + (y2 - y1)^2 + (z2 - z1)^2)