The prisoners dilemma

Two prisoners are chained to the walls of a triangular cell. The base is covered with a mirror and a perpendicular wall is separating them. They can each see the opposite corner through a hole. Proof they can see each other through another hole at the base of the perpendicular.

Note that this problem is known as the Blanchet Theorem.

Scroll down for a solution to this problem.


Solution by Lewis Corner.
Solution by Dmitriy Spiridonov.

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