All of Trigonometry in 38 Minutes: Top 10 Must Knows, from Similar Triangles to Trig Equations

One complete exam lesson for High-school trigonometry for GCSE, IGCSE, SAT, ACT, AP Precalculus, A-Level, IB, VCE, HSC, NCEA and SPM. In this lesson: Must know 1 · Similar triangles, Must know 2 · SOH-CAH-TOA, Must know 3 · Sine law and cosine law, Must know 4 · Special triangles, Must know 5 · Unit circle and CAST, Must know 6 · Angles bigger than 90°, Must know 7 · Sine and cosine graphs, Must know 8 · Radians, Must know 9 · Identities, Must know 10 · Solving trig equations. Then practice questions, a full model answer and a summary. One full lesson, about 37 minutes, with every step worked on screen so you can pause and try first. Exam: High-school trigonometry for GCSE, IGCSE, SAT, ACT, AP Precalculus, A-Level, IB, VCE, HSC, NCEA and SPM. What's covered (chapters): 0:00 What this lesson is 1:40 Must know 1 · Similar triangles 4:22 Must know 2 · SOH-CAH-TOA 6:53 Must know 3 · Sine law and cosine law 9:42 Must know 4 · Special triangles 12:21 Must know 5 · Unit circle and CAST 15:21 Must know 6 · Angles bigger than 90° 18:02 Must know 7 · Sine and cosine graphs 20:33 Must know 8 · Radians 22:50 Must know 9 · Identities 24:55 Must know 10 · Solving trig equations 26:48 Where students lose marks 27:47 Practice set A 30:17 Practice set B 32:42 Full model answer 34:59 Summary and close Who it's for: Students sitting this paper in 2026 who want one structured revision lesson with worked practice, plus teachers and tutors looking for a full-topic recap. How to use it: pause before each worked answer, try it yourself, then check. Eurekha is not affiliated with, and this video is not endorsed by, any exam board, ministry or education authority named here. All questions are original. Always check the official documents and timetable for your own exam. ▶ Watch next: Singapore N(A) Maths 4045 Revision 2026: Algebra, Circles, Trigonometry, Mensuration & Statistics    • Singapore N(A) Maths 4045 Revision 2026: A...   🔔 Subscribe to Eurekha for free full-length exam lessons:    / @eurekha-c1g   If this helped, like the video and share it with a classmate. About Eurekha: free, exam-focused lessons in maths, science, English and computing, made in Melbourne, Australia for students following any curriculum worldwide. #Maths #ExamPrep #Revision