Mathematics · a topic
Circle theorems, Taught not just answered.
A real-time, 1:1 lesson on Circle theorems: an AI teacher explains it out loud while it visualizes every step. Interrupt it, ask why, and it checks you got it, in 26 languages.
The idea
What is Circle theorems?
Circle theorems are a set of results about angles and lengths formed by chords, tangents and radii in a circle. Key ones: the angle at the centre is twice the angle at the circumference on the same arc; angles in the same segment are equal; the angle in a semicircle is a right angle; opposite angles of a cyclic quadrilateral are supplementary; a tangent meets a radius at a right angle; the alternate segment theorem links the tangent-chord angle to the inscribed angle.
Where it appears: Class 9 and 10 CBSE and ICSE, GCSE and IGCSE, IB MYP, foundation geometry for olympiads.
Where learners get stuck
Why Circle theorems is hard
Learners cannot see which theorem applies in a busy diagram, and they confuse angles subtended by the same arc with angles standing on different arcs, or assume a line is a diameter when it is only a chord.
The picture a good explanation starts with: A circle with centre marked, one arc highlighted, the angle at the centre and the angle at the circumference on that arc both drawn and the doubling relation labelled.
A lesson, step by step
How a lesson on Circle theorems goes
01
Ask
Type or say "How do I spot which circle theorem to use?" in your own words, in any of 26 languages.
02
Plan
The tutor plans a storyboard, one picture per idea, starting with a circle with centre marked, one arc highlighted, the angle at the centre and the angle at the circumference on that arc both drawn and the doubling relation labelled.
03
Explain
It explains Circle theorems out loud while the picture builds step by step, pitched to your level (Class 9 and 10 CBSE and ICSE and up).
04
Interrupt
Say "wait, why?" or type a doubt: it stops, answers over the picture, and carries on. Ask for a different explanation any time.
05
Check
A checkpoint question makes sure the idea landed, and Tests keep the practice going.
06
Your notes
Upload a PDF or a photo of your class notes or a past paper and the lesson follows your textbook's terms.
Ask it anything
Questions learners ask about Circle theorems
- How do I spot which circle theorem to use?
- Why is the angle at the centre twice the angle at the circumference?
- What does the alternate segment theorem actually say?
Any of these, or your own, typed or spoken. The tutor answers on the picture and adapts to how well you are following.
Questions
Asked, Answered
Can LetMeTeach explain Circle theorems?
Yes. Ask in your own words and the tutor plans a lesson on Circle theorems: it starts with a circle with centre marked, one arc highlighted, the angle at the centre and the angle at the circumference on that arc both drawn and the doubling relation labelled. Then it explains each step out loud as the picture builds, stops when you say "wait, why?", and ends with a checkpoint question.
Where does Circle theorems come up?
Class 9 and 10 CBSE and ICSE, GCSE and IGCSE, IB MYP, foundation geometry for olympiads. The lesson is pitched to your level and the exam or curriculum you follow, and you can upload your own notes or past papers so it uses your textbook's terms.
Can I learn Circle theorems in my own language?
Yes. LetMeTeach teaches in 26 languages and plans the lesson in the language you choose rather than translating an English one, so the terms match what your textbook says. The Free plan includes 7 hours a month with no card.
Last updated
Learn Circle theorems, Starting now.
Ask "How do I spot which circle theorem to use?" and watch the answer drawn. The Free plan needs no card.