When working on RS Aggarwal's Class 11 Chapter 15, students need to pay close attention to the concepts because all of the questions are based on what is taught in the chapter. Before starting to work on Chapter 15 Trigonometric and Circular Functions from Class 11 RS Aggarwal, students should pay close attention to the following ideas: T-ratios or trigonometric ratios are the relationships between the different angles or sides of a right angle triangle. Angles are the main focus of trigonometric functions, which are simple functions. Sine, Cosine, Tangent, Cotangent, Secant, and Cosecant are some of these trigonometric functions. Angles that add up to a compound angle are called constituent angles. Trigonometric functions can be used in many different ways.