# Lessons In Electric Circuits -- Volume V

# Chapter 5

# TRIGONOMETRY REFERENCE

__Right triangle trigonometry__

A *right triangle* is defined as having one angle precisely equal to 90^{o} (a *right angle*).

__Trigonometric identities__

H is the *Hypotenuse*, always being opposite the right angle. Relative to angle x, O is the *Opposite* and A is the *Adjacent*.

__The Pythagorean theorem__

__Non-right triangle trigonometry__

__The Law of Sines (for __*any* triangle)

__The Law of Cosines (for __*any* triangle)

__Trigonometric equivalencies__

__Hyperbolic functions__

Note: all angles (x) must be expressed in units of *radians* for these hyperbolic functions. There are 2π radians in a circle (360^{o}).

*Lessons In Electric Circuits* copyright (C) 2000-2003 Tony R. Kuphaldt, under the terms and conditions of the Design Science License.