Distance of closest Approach

The distance of closest approach in the context of vectors refers to the minimum distance between two lines in three-dimensional space.

Its basis is derived from finding some vector normal to a plane or line that most closely approaches the target point. There exists variants in finding the normal vector, but the most common ones are:

• For a plane to a point, the normal vector is the normal vector of the plane itself.
• For a line to a point, the normal vector is the dot product of the direction vector of the line and the vector from the point to any point on the line.

Distance from a Plane to a Point

Distance from a Line to a Point