Circle Theorems

A collection of excellent free resources for demonstrating the various circle theorems:
Tim Devereux has created GeoGebra applets which allow exploration of the circle theorems. You can access each theorem from the menu on the left which includes a useful summary of all the theorems.

GeoGebra - Circle Theorems

GeoGebra – Circle Theorems

See also these excellent demonstrations or try the following from Suffolk Maths.

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GeoGebra is software for interactive geometry. Astonishingly is it free, astonishing as it is such of such high quality and is so well supported. There are many resources available on the Internet. I have created a Diigo list of resources which includes many examples and tutorials.

Circle Theorem GeoGebra

GeoGebra is excellent for studying circle theorems

Note that if you have not used GeoGebra before the Introductory book is very helpful. Also, see in particular Guillermo Bautista’s Mathematics and Multimedia Blog for numerous tutorials from beginner to advanced and the GeoGebra YouTube Channel.