Cuemath
Cuemath: Trigonometry
A comprehensive guide for learning all about the basics of trigonometry, the various identities-formulas of trigonometry, solved examples, and practice questions.
Purple Math
Purplemath: Using Identities to Evaluate
Demonstrates how to evaluate trigonometric functions by using trig identities.
Purple Math
Purplemath: Trigonometric Identities
Lists the basic trigonometric identities, and specifies the set of trig identities to keep track of, as being the most useful ones for calculus.
Purple Math
Purplemath: Solving Simple (To Medium Hard) Trig Equations
Introduces techniques for solving trigonometric equations. Provides worked examples of solving some simpler to medium-hard equations.
Wolfram Research
Wolfram Math World: Trigonometric Functions
This site provides a listing of the trigonometric functions and their inverses. Their notation is also addressed along with links to each of the fundamental trigonometric functions.
Windstream
Ojk's Pre Calculus Study Page: The Four Other Trig Functions
Trigonometry ratios and their signs are given in this explanation of the other trig functions. Graphs of tangent, cotangent, secant, and cosecant are given. Examples are included.
Windstream
Ojk's Precalculus Study Page: Trigonometry Sample Test
A practice test that covers proving trigonometric identities and solving advances trigonometric equations.
Windstream
Ojk's Precalculus Study Page: More Difficult Trig Equations
An introduction to solving trigonometric equations by using the reciprocal, negative, Pythagorean, and cofunction identities. Includes several examples and exercises with solutions at the bottom of the page.
Wolfram Research
Wolfram Math World: Trigonometry
This site provides a good definition of trigonometry. Includes many links to key terms and many more to related terms. This site may be used as a refresher for students who have finished the course, or students currently studying the...
Math Medics
S.o.s. Math: Trigonometry
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.
Math Words
Math Words: Cofunction Identities
This MathWords.com site, which is a glossary of math terms, shows the relationship in radians and degrees between sin and cos, tan and cot, and sec and csc.
Other
Technical Tutoring: The Very Fast Trig Review
This resource is a quick review of the functions and identities in trigonometry.
Other
Technical Tutoring: Trigonometry: The Very Fast Review
This site is a quick review of the functions and identities in trigonometry. Very helpful site.
Other
Technical Tutoring: Trig Identities
This resource is a quick review of the functions and identities in trigonometry.
Math Medics
S.o.s. Math: Solving Trigonometric Equations
This lesson contains trigonometric equations of various forms that you can solve. The problems contain the answers solved in three different ways: algebraically, graphically, and using the concept of equivalence.
Math2
Math2.org: Trigonometric Identities
This personal site is a listing of numerous trig identities. A great reference site.
Free Math Help
Free Math Help: Trigonometry Derivatives
The tutorial examines trigonometric derivatives. Formulas, graphs, and an example are included.
Free Math Help
Free Math Help: Double and Half Angle Formulas
Students learn about the double and half angle formulas. Definitions and formulas are included.
Varsity Tutors
Varsity Tutors: Hotmath: Algebra Review: Trigonometric Ratios
Find a quick, concise explanation of the trigonometric ratios: sine, cosine and tangent. Examples are given and clearly explained.
Interactive Mathematics
Interactive Mathematics: The Right Triangle and Applications
Learn how to "solve" a right triangle and apply the concept to real world situations using angles of elevation and depression.
Interactive Mathematics
Interactive Mathematics: Sine, Cosine, Tan & Reciprocals
The definitions of the six trig ratios are presented here, along with several examples of how to determine the ratios given 2 or more sides of a right triangle.
Other
Summary of Trigonometric Identities
A complete list of the important identities from high school trigonometry, complete with a set of exercises.
Free Math Help
Free Math Help: Trigonometry Addition Formulas
Students learn about the trigonometric addition formulas. Sine, cosine, and tangent formulas are included.
eFunda
E Funda: Multiple Angle
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.