Angles

An angle is a figure formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex of the angle.

Types of Angles

  1. Acute Angle: An angle whose measure is less than 90 degrees.
  2. Right Angle: An angle whose measure is exactly 90 degrees.
  3. Obtuse Angle: An angle whose measure is greater than 90 degrees but less than 180 degrees.
  4. Straight Angle: An angle whose measure is exactly 180 degrees.
  5. Reflex Angle: An angle whose measure is greater than 180 degrees but less than 360 degrees.
  6. Full Angle: An angle whose measure is exactly 360 degrees.

Measurement

Angles are measured in degrees (°), radians (rad), or grads (g). In most mathematical work beyond practical geometry, angles are typically measured in radians rather than degrees. This is because radians have a mathematical "naturalness" that leads to a more elegant formulation of a number of important results.

Applicationsp

Angles are fundamental in the study of trigonometry, geometry, physics, engineering, and many other fields. They are used to define the trigonometric functions (sine, cosine, etc.), measure rotation, define direction, and much more.