Circle Theorems for GCSE + IGCSE Maths
Circle Theorems are a big topic for both GCSE and IGCSE Mathematics, and here you can find everything you need to know to learn both how and why they work. In this comprehensive guide you’ll learn about
- Angles at the centre and circumference
- Angles in the same segment
- Angles in cyclic quadrilaterals
- Properties of tangents
- The alternate segment theorem
- Intersecting chords theorem
Each theorem is explained clearly with animated videos to bring the theorems to life, including detailed diagrams and examples. You can learn about the main theorems in the first video, their proofs in the second video, and the intersecting chords theorems (with proofs) in the third.
Circle Theorems Explained
This video explains all the main circle theorems, brought to life with animations of both the results and some GCSE and IGCSE style example problems.
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Circle Theorem Proofs
Go deeper with this video, and understand the ‘why’ behind the circle theorems, with all cases covered and beautifully animated proofs at every stage.
Intersecting Chords Theorem (Power of a Point)
The final video in this series covers the intersecting chords and secants theorems, sometimes known as the ‘Power of a Point’ theorems, and includes full proofs and examples.