Trigonometric Functions: Sin and Cos

This lecture covers the definition of trigonometric functions, specifically the sine and cosine functions, and their inverses. It explains how these functions are related to the unit circle, introduces the notation for sine and cosine, defines the functions, provides examples of their values, and discusses the Pythagorean relation. The lecture also explores the graphs of the sine function, notable points on the sine curve, the behavior of sine and cosine in terms of growth and decline, and concludes with a summary of the key concepts learned.