Introduction to Projective Geometry via Tic-Tac-Toe Grids #SoME2

My entry for @3blue1brown's Summer of Math Exposition 2022. It's my first video ever and there are a million things I would like to improve. Mostly the audio quality and my terrible, terrible accent. 😅 Alas, perfect is the enemy of the good, isn't it. So, here we go. #SoME2 -------------------------------- Animations were made with CindyJS: For more information on Projective Geometry, I recommend the book Perspectives in Projective Geometry by Jürgen Richter-Gebert: -------------------------------- Chapters: [00:00] Opening [00:40] Introduction [01:48] Projective Transformations [04:10] Incidence Construction [06:55] The Cross-Ratio [16:33] The “School” Method [19:33] Epilogue