Other
Brown Math: Remembering Trig Identities
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...
McGraw Hill
Glencoe: Online Study Tools: Quiz on Basic Trigonometric Identities
Students show comprehension of advanced mathematical concepts in Trigonometry. The online quiz assesses the scholars on basic trigonometric identities.
Varsity Tutors
Varsity Tutors: Hotmath: Practice Problems: Fundamental Trigonometric Identities
Twenty problems present a variety of practice working with fundamental trigonometric identities. 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 "View...
CK-12 Foundation
Ck 12: Trigonometry: Composition of Trig Functions and Their Inverses
[Free Registration/Login may be required to access all resource tools.] How to Compose a trigonometric function.
CK-12 Foundation
Ck 12: Trigonometry: Proofs of Trigonometric Identities
[Free Registration/Login may be required to access all resource tools.] Simplifying trigonometric expressions using identities
Government of Alberta
Learn Alberta: Math Interactives: Exploring Trigonometry (Video Interactive)
This multimedia Learn Alberta math resource looks at how trigonometry is used in making sure that airplanes land safely at airports. The accompanying interactive component gives students practice in using trigonometric ratios, namely...
Curated OER
Trigonometry Realms
Excellent site reviewing the realms of Trigonometry. Topics Include the trig functions, graphs, right triangles and much more.
Math Words
Math words.com: Trig Identities
This MathWords.com site lists the equations for all of the trigonometric identities.
CK-12 Foundation
Ck 12: Geometry: Inverse Trigonometric Ratios
[Free Registration/Login may be required to access all resource tools.] Use the inverse trigonometric ratios.
CK-12 Foundation
Ck 12: Trigonometry: Trigonometric Functions and Angles of Rotation
[Free Registration/Login may be required to access all resource tools.] Describing trig functions as relationships on the unit circle.
CK-12 Foundation
Ck 12: Trigonometry: Trigonometric Functions of Negative Angles
[Free Registration/Login may be required to access all resource tools.] Learn how to define trigonometric functions of angles with negative values.
CK-12 Foundation
Ck 12: Composition of Inverse Reciprocal Trig Functions
[Free Registration/Login may be required to access all resource tools.] On this site students learn about the composition of inverse trigonometric functions. Students read about inverse reciprocal functions, watch a video about the topic...
CK-12 Foundation
Ck 12: Trigonometry: Cofunction Identities and Reflection
[Free Registration/Login may be required to access all resource tools.] Find different trigonometric functions that have the same values for a given angle.
CK-12 Foundation
Ck 12: Trigonometry: Quotient Identities
[Free Registration/Login may be required to access all resource tools.] Illustrates identities found from dividing two trigonometric functions.
University of Vienna (Austria)
University of Vienna: Trig Functions With Absolute Value Differentiable or Not?
Given eight trigonometric functions containing absolute value elements, choose whether each is differentiable or non-differentiable. At the conclusion of the exercises, the site returns a score which helps judge understanding of the topic.
CK-12 Foundation
Ck 12: Trigonometry: Trigonometric Identities and Equations
[Free Registration/Login may be required to access all resource tools.] Describe general forms and graphs for cosine and sine equations.
CK-12 Foundation
Ck 12: Trigonometry: Pythagorean Identities
[Free Registration/Login may be required to access all resource tools.] Defining trigonometric identities that rely on the Pythagorean Theorem.
Purple Math
Purplemath: Inverses of Trigonometric Ratios
You know that you can take side lengths and find trig ratios, and you know you can find trig ratios (in your calculator) for angles. What is missing is a way to go from the ratios back to the original angles. And that is what "inverse...
McGraw Hill
Glencoe: Online Study Tools: Quiz on Verifying Trigonometric Identities
Students show understanding of advanced mathematical concepts in Trigonometry. The online quiz tests the scholars on verifying trigonometric identities.
Math2
Math2.org: Trigonometric Identities
This personal site is a listing of numerous trig identities. A great reference site.
Windstream
Ojk World of Math: Relationships Between the Functions
This tutorial discusses relationships among all the trig identities. Examples are given on how to apply them to simplify trig expressions and prove identities.
CK-12 Foundation
Ck 12: Trigonometry: Inverses of Trigonometric Functions
[Free Registration/Login may be required to access all resource tools.] Here you'll learn how to find the domain and range of inverse trigonometric functions by utilizing the reflection principle.
University of Vienna (Austria)
Univ of Vienna: Trigonometric Functions
An interactive tool to discover how the trig functions came to be. Applets are used in this interactive learning tool. Examples exercises are also given.
CK-12 Foundation
Ck 12: Definition of the Inverse of Trigonometric Ratios
[Free Registration/Login may be required to access all resource tools.] Explain the inverse of trigonometric functions.