Uploaded November 2025 | Updated September 2026, 2 weeks ago

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What is the smallest circle that encloses three touching coins? Oxbridge Mathematician Dr Tom Crawford explains the solution with some help from GXWeb - try it for free here: https://gxweb.app

Thank you to Saltire Software for partnering in this video. Check out the free browser-based interactive geometry software GXWeb here: geometryexpressions.com/gxweb

The more advanced Windows version with extra features - Geometry Expressions - can be accessed here: geometryexpressions.com/gx/explore/index.html

Produced by Dr Tom Crawford at the University of Oxford. Tom is Public Engagement Lead at Oxford University Lifelong Learning: conted.ox.ac.uk/profiles/tom-crawford

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