sin(x) and Unit Circle Animation

This example demonstrates the relationship between the sine function sin(x) and the unit circle through animation, visually showing how the sine value changes with the angle. Core mathematical concepts include the unit circle, trigonometric functions, and the relationship between angles and coordinates. It uses GeoGebra commands/objects like Vector, c, α, A/B, a/D/u, β, and text1-4. Suitable for high school mathematics teaching to help students understand the definition of trigonometric functions and the application of the unit circle.