If two projectiles are launched simultaneously at the same speed, but different angles so that they land on each other's launch points, what is the distance of their closest approach in the air?
0:00 - Introduction
1:40 - Kinematics
3:21 - Geometric constraint
4:56 - Relative position
8:34 - Minimizing the distance (finding the time)
9:51 - The minimal distance
