Stage 29 · Spatial Vectors & Solid Geometry

29.3.1 The Direction Vector of a Line

29.3 Seeing Parallel and Perpendicular with Vectors — Direction and Normal Vectors

Point 1 of 6

29.3.1 The Direction Vector of a Line

Core idea

Whichever way a line points, use an arrow d aimed the same way to stand in for the whole line.

Module goal. Translate lines and planes into two handy "keys," the direction vector and the normal vector, and use vectors being collinear or perpendicular to settle parallelism and perpendicularity among lines and planes.
eastmath.com · 29.3 Seeing Parallel and Perpendicular with Vectors — Direction and Normal Vectors · 29.3.1 The Direction Vector of a Line