Simple geometric position

The calculation and proof of solid geometry often involve two problems: one is the position relation, which mainly includes line perpendicularity, line plane perpendicularity, line line parallel, line plane parallel; The second is the measurement problem, which mainly includes the distance from the point to the line, the point to the surface, the Angle formed by the line, the Angle formed by the surface, and so on. There are many examples here that use vectors to prove the vertical of lines and lines and calculate line angles, and how to use vectors to prove parallel lines and planes, calculate the distance from the point to the plane, line angles and Angle angles are not many, which play a role in introducing jade.