1. Draw the rotated rotor R2 R1 R- 2 as an arc in the spherical image. (Hint: What would you expect it to be based on its geometric meaning? Warning: It is not simply the R1 arc rotated over the R2-arc!)
2. Establish the precise correspondence between the quantities in the rotor composition (7.9) and the quaternion product of (7.11). (Warning: This is a painful exercise in keeping things straight, and not very rewarding.)