Stage 29 · Spatial Vectors & Solid Geometry
29.4.3 The Dihedral Angle and Its Vector Description
29.4 Measuring Angles with Vectors — Line–Plane and Dihedral Angles
Point 3 of 5
29.4.3 The Dihedral Angle and Its Vector Description
Core ideaTwo half-planes are like an open book, and the angle between them is pinned down by the angle between the two faces' normal vectors.
Module goal. Use the angle formulas for direction and normal vectors to turn abstract spatial angles into coordinate calculations, working out angles between lines, between a line and a plane, and dihedral angles in a systematic way.