Part of Eric Weisstein's comprehensive math site, this page deals with double-angle formulas. This site includes traditional trigonomic double-angle functions as well as hyperbolic trigonometric function. Includes links to related terms...

Twenty-two problems present a variety of practice working with double-angle and half-angle formulas. They are given with each step to the solution cleverly revealed one at a time. You can work each step of the problem then click the...

Double angles and half angles are explained through step by step examples. The steps are clear and easy to follow.

The mathematics session examines angle sum, angle difference, double angle, and half angle formulas. The tutorial includes class notes, examples, and practice problems with solutions. The teacher resource investigates how the formulas...

[Free Registration/Login may be required to access all resource tools.] Derivation of double angle identities for sine, cosine, and tangent.

Resource provides trigonometry formulas for unit circle, reciprocal identities, ratio identities, Pythagorean identities, sum and difference formulas, and double-angle formulas.

Students learn about the double and half angle formulas. Definitions and formulas are included.

This tutorial introduces the double-angle and half-angle formulas for sine, cosine, and tangent, and gives sample application and proof exercises. Assumes knowledge of the sum and difference formulas.

This tutorial offers formulas and explanations on trigonometric addition formulas and features an easy way to remember the sine and cosine addition formulas using matrices.

The University of Saskatchewan provides an explanation of trigonometric identities, including the reciprocal identities, the addition and subtraction formulas with sine and cosine, and the double angle formulas. There are links to...

At this site from eFunda you can scroll to the middle of the page for a listing of multiple angle formulas for cos, sin, and tan.

This lesson is the main SOS Math page for trigonometry. Surf the lesson to find most any trigonometric identity, formula, and many forms of help in the area of trigonometry.

Faced with a large number of trigonometric identities, students tend to try to memorize them all. This site the emphasis is on understanding how the functions work and on memorizing only about a half dozen of them - all the others work...

This tutorial highlights the numerous trigonometric identites (but does not define the basic trigonometric functions).

This resource clearly and thoroughly explains the many types of trigonometric identities. There are example problems solved, problems for the student to attempt, and answers to the student problems.

This site from MathWorld explains the hyperbolic function. The information is not too in-depth, but factual and quite a few links are provided for additional information on related subjects.