2022 TTs SA7
Source: 2022 Tournament of towns Spring Senior A-level
May 14, 2022
3D geometrygeometry
Problem Statement
A starship is located in a halfspace at the distance from its boundary. The crew knows this but does not know which direction to move to reach the boundary plane. The starship may travel through the space by any path, may measure the way it has already travelled and has a sensor that signals when the boundary is reached. Is it possible to reach the boundary for sure, having passed no more than:?