Sine cosine tangent

Math

Definition

The three primary trigonometric ratios for a right triangle. Sine is the ratio of the opposite side to the hypotenuse, cosine is adjacent over hypotenuse, and tangent is opposite over adjacent. These ratios are the foundation of trigonometry.

Examples

  • In a right triangle with opposite = 3, adjacent = 4, hypotenuse = 5: sin = 3/5, cos = 4/5, tan = 3/4
  • Finding the height of a building by measuring the angle of elevation and distance from the base
Key Fact

SOH-CAH-TOA: Sin = Opposite/Hypotenuse, Cos = Adjacent/Hypotenuse, Tan = Opposite/Adjacent

Related Terms

Soh-cah-toa Solving right triangles Unit circle Reference angles

Study This Concept

Practice sine cosine tangent with free review games in these units:

Geometry Unit 8: Right Triangles and Trigonometry