Access the official NCERT Class 10 Mathematics textbook for Chapter 8 – Introduction to Trigonometry PDF. This chapter opens the world of trigonometric ratios—defining sine, cosine, tangent (and their reciprocals) in right-angled triangles. It explains standard angles, complementary-angle identities (e.g., sin(90°–θ)=cos θ), and fundamental Pythagorean identities like sin²θ + cos²θ = 1. You’ll also learn how to apply these ratios in real-world height and distance problems, making trigonometry both practical and powerful.
Chapter Highlights:
- Definition and scope of trigonometry in right‑angled triangles
- Trigonometric ratios: sin, cos, tan and reciprocals sec, cosec, cot
- Trigonometric ratios of standard angles (0°, 30°, 45°, 60°, 90°)
- Complementary-angle identities: e.g., sin(90°–θ)=cos θ, tan(90°–θ)=cot θ
- Pythagorean identities: sin²θ + cos²θ = 1, sec²θ – tan²θ = 1, etc.
- Using SOH‑CAH‑TOA for solving side‑angle‑side problems
- Introduction to height & distance problems using trigonometric ratios