I have been self-studying trig using (first) the Khan Academy [trig course](https://www.khanacademy.org/math/trigonometry). Here is a path through it if you want to revise and/or study yourself. # Basics 1. [[Basic Trigonometric Functions]] 2. [[Inverse Trigonometric Functions]] 3. [[Trig Ratios of Special Triangles]] 4. [[Trigonometric Functions of Complementary Angles]] 5. [[Pythagorean Trigonometric Identities]] 6. [[Unit Circle Definitions of Trigonometric Functions]] 7. [[Radians]] 8. [[Trigonometry Rote Learning]] is a cheat sheet I'm putting together for things I just want to learn to save myself some time. I've been using ankiweb for this and will link my deck when I feel it's in a good place. # Some Identities (far from exhaustive!) 1. [[Geometric Construction of Trigonometric Identities from the Unit Circle]] 2. [[Trigonometric Identities from Rotation]] 3. [[Double Angle Identities]] 4. [[Half Angle Identities]] 5. [[Law of Sines and Law of Cosines]] 6. [[Sum and Difference Identities]] # Some properties of trigonometric functions 1. [[Sinusoidal Functions and their Graphs]] 2. [[Amplitude, Period and Midline of Trigonometric Expressions]] 3. [[Inverse Trigonometric Functions]] 4. [[Other Trigonometric Functions and their graphs]] # Other related stuff 1. [[Trigonometric Substitution in Calculus]] 2. [[Circles and their Equations]] 3. [[Vectors]] 4. [[Polar Coordinates]] ## Books 1. "[Trigonometry Essentials Practise Workbook with Answers](https://www.amazon.co.uk/Trigonometry-Essentials-Practice-Workbook-Answers/dp/1477497781/ref=sr_1_1?crid=ZTBU0GGQDBPE&keywords=trigonometry+essentials+practice+workbook+with+answers&qid=1695188813&sprefix=trigonometry+e%2Caps%2C82&sr=8-1)" by Chris McMullen. This is helpful for giving tons of practise exercises to just get used to each of the concepts. It tackles things in a different order from above.