Pythagorean Identity

sin2θ+cos2θ=1\sin^2\theta + \cos^2\theta = 1

Description

Fundamental trigonometric identity relating sine and cosine.

Variables

Symbol Meaning
θ Angle
sin²θ Sine squared
cos²θ Cosine squared

Example

Problem

Verify for θ=30°

Solution

(0.5)² + (0.866)² ≈ 1

Real-World Applications

  • Trigonometric simplification
  • Calculus
  • Physics