This MathWords.com site lists the equations for all of the trigonometric identities.

Given the sine (or cosine) of an angle, find its cosine (or sine) using the Pythagorean identity. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

[Free Registration/Login may be required to access all resource tools.] Use the Pythagorean Theorem to find a right triangle's missing side lengths.

Lists the basic trigonometric identities, and specifies the set of trig identities to keep track of, as being the most useful ones for calculus.

The purpose of this task is to use the Pythagorean Theorem to establish a fundamental trigonometric identity for an acute angle. The reasoning behind this identity is then applied to calculate a cosine for a given obtuse angle. Aligns...

Learners explore trigonometric identities. Definitions of the Pythagorean, reciprocal, tangent, and negative identities are included.

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

Looking for a 10-minute review of the major concepts of trigonometry? This site is a quick recap of degrees and radians, SOH CAH TOA, Pythagorean identities, and special right triangles are all found here.

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

[Free Registration/Login may be required to access all resource tools.] This lesson applies the trigonometric ratios and their inverses to real-life situations.

[Free Registration/Login may be required to access all resource tools.] Determine if three side lengths make a right triangle, and given the length of its legs, find the length of a right triangle's hypotenuse.

In this task, young scholars investigate polynomial identities in order to generate Pythagorean triples. Aligns with A-APR.C.4.

College professor Dan Bach reviews basic trig concepts, including trig functions, right triangles, circles, radians, and polar coordinates. Site includes animated graphs and detailed examples.

In addition to understanding the concept of similar right triangles and how they apply to trigonometric ratios, students explore a clinometer app, and discover how it can be used to test the mathematics underpinning trigonometry.

This site examines the six trigonometric functions from a right triangle point of view. Provides information, examples, and lots of exercises for understanding.

Great application of trig and introduction to the trig functions. Also found here are the Law of Sines and Law of Cosines as well as other trig topics to review.

Guide a mummy safely through the burial chambers of a pyramid as you solve length and area problems in basic to advanced geometry. There are four game zones that deal with circles and triangles, quadrilaterals, the Pythagorean Theorem,...

The goal of this task is to study some values of sin x and cos x for different angles, and to look for and then explain patterns that are seen. Aligns with HSF-TF.C.8.

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.

In this task students are asked to combine numerous skills to create a miniature golf hole. Students create a scale drawing of the hole, calculate the area of the hole and determine the percentage of total area used. In addition,...