Triangle Relations: Cosine and Sine Laws

This lecture delves into the relationships within an arbitrary triangle, introducing the Cosine Law and the Sine Law as generalizations of the Pythagorean Theorem. The instructor explains how to apply these laws to find side lengths and angle measures in different scenarios, emphasizing the importance of understanding when to use each law and the potential pitfalls of relying solely on the Sine Law. Through detailed examples and calculations, students learn how to determine angles using the Cosine Law and how to handle cases where two sides and an angle are known. The lecture concludes with a practical exercise to reinforce the concepts discussed.