Trigonometric Identities Teacher Resources

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...

A couple of more examples of using Trig functions to solve the sides of a triangle. This video use the basic trigonometric functions to determine unknown side lengths of a right triangle. Example shows using trigonometry as well as the...

Provides trigonometric identities, which include fundamental identities, even-odd identities, addition formulas, double-angle formulas, subtraction formulas, product-sum formulas, and identities for sin squared and cos squared.

The purpose of this task is to apply translations and reflections to the graphs of the functions f(x)=cos x and g(x)=sin x in order to derive some trigonometric identities. There are also rotations 180 degrees about points on the x-axis...

Video showing how to derive two basic trigonometric identities.

An "identity" is a tautology, an equation or statement that is always true, no matter what. Proving an identity is very different in concept from solving an equation. This resource demonstrates some useful techniques for proving...

Students show comprehension of advanced mathematical concepts in Trigonometry. The online quiz assesses the scholars on basic trigonometric identities.

The mathematics tutorial verifies trigonometric identities. The tutorial consists of several examples with detailed solutions.

Video about finding the equation of a trigonometric function from its graph. Two examples are sine functions and one example is a cosine function [9:52]

Video showing how to graph the sine and cosine functions from their equations with modifications to the amplitude and period. Also gives an example of determining the trigonometric function using the features of the graph. Includes link...

A collection of lessons and practice exercises on trigonometric ratios. Students will learn how to solve for an angle and for a side, and to apply trigonometry in setting up and solving word problems.

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...

This site reviews basic information on inverse functions and inverse notation. Graphs of inverse trig functions are shared and discussed.

This list of trigonometric identities includes the factoring formulas near the bottom. A great tool for reference.

Continuation of video lesson using the basic trigonometric functions to determine unknown side lengths of a right triangle. Example shows using trigonometry as well as the Pythagorean Theorem to find the length of the third side of the...

Video using the basic trigonometric functions to find the length of a side in a right triangle. Examples are given with angle measures in radians. Includes link to additional practice problems. [10:03]

[Free Registration/Login may be required to access all resource tools.] How to Compose a trigonometric function.

This Clark University page is an excellent reference page for trig identities. It is a little difficult to read so take your time with the formulas. If you remember soh - cah - toa, the other formulas are right here.

Define the trigonometric ratios in terms of ratios of the sides of a right triangle.

Use a right triangle to identify the six trigonometric ratios such as cosine, sine, tangent, co-secant, secant, and cotangent. Assess learning with a quiz. [6:54]

[Free Registration/Login may be required to access all resource tools.] Use the inverse trigonometric ratios.

A good introduction to trigonometric identities, equations that are always true for a right triangle and require knowledge of the functions sine, cosine, and tangent.

In this section we will give a quick review of trig functions. We will cover the basic notation, relationship between the trig functions, the right triangle definition of the trig functions. We will also cover evaluation of trig...

[Free Registration/Login may be required to access all resource tools.] Simplifying trigonometric expressions using identities