Learn about and revise the different angle properties of circles described by different circle theorems with GCSE Bitesize Edexcel Maths.

Mathematicians at Monash University have cracked a centuries-old puzzle dating back to the 17th century, extending Descartes’ Circle Theorem into a bold new territory.

The mathematical concepts involved, circles and radii, are basic ones that have stood the test of time. However, Johnson’s theorem comes up short in the beauty department in one salient respect.

Circle theorems are properties that are true for all circles, regardless of their size. There are six theorems to learn and recognise.

They are often gems that provide a new proof of an old theorem, a novel presentation of a familiar theme, or a lively discussion of a single issue. Building on two centuries' experience, Taylor & ...

Descartes’ theorem, a cornerstone of geometry, defines the relationship between four mutually tangent circles. But for centuries, generalizing the equation to more than four circles had eluded ...