Angles

I) Angle between two planes: let the planes

Then:

II) Angle between a plane and a straight line: let

Then:

III) Angle between two straight lines: let

Then:

Exercise: let:

a) Study the relative position between π and π' and the angle they form.

b) Study the relative position between π and r and the angle they form.

Solutions: a) Intersecting planes, angle = 72º32'33''; b) Intersecting ones, angle = 15º15'18''