1. The problem statement, all variables and given/known data Finding lightpaths with given starting and ending points via one or more mirrors. In those kind of problems you try image someone pointing a laser with a very narrow beam at a certain direction to the mirror, so it will reach point B. For example: You are seeing a square mirror room (with mirrorwalls a, b, c, d) where you point from point A via the mirrors c, b, d and a to point B. A sketch can be made easily made. In order to find a more accurate solution, we flip the base cell with the points A and B a few times as shown in the image. After the mirroring is done, the line connecting A is drawn towards the mirror image B '. Question: Construct the path in the original square. Complete the drawing. 2. Relevant equations mirror images 3. The attempt at a solution What do I need to do with those virtual squares? And why is the line drawn from A to B' through those other rooms?