Trigonometric functions | Trigonometry | Math | Khan Academy Discover how to measure angles, distances, and heights using trigonometric ratios and the unit circle Learn how to use sine, cosine, and tangent to solve real-world problems involving triangles and circular motion
Unit circle trigonometry | Lesson (article) | Khan Academy What are unit circle trigonometry problems? The problems in this lesson involve circles and angle measures in radians, a unit for angle measure much like degrees We can use radian measures to calculate arc lengths and sector areas, and we can calculate the sine, cosine, and tangent of radian measures