Lecture
This lecture covers the trigonometric functions sine and cosine, their inverses, and the concept of the right triangle. It explains the notations for a right triangle, introduces the sine and cosine of angles, discusses trigonometric ratios in a right triangle, and presents examples of solving triangles. The lecture also explores trigonometry in isosceles and equilateral triangles, as well as the values of sine and cosine for specific angles. It concludes with remarks on additional trigonometric tools and equations involving sine and cosine. Overall, the lecture provides a comprehensive overview of trigonometry in the context of right triangles.