Government of Alberta
Learn Alberta: Exploring Similarity and Congruence
Begin by watching this captivating video showing how the concepts of similarity and congruence are found in road signs. Following the video [1:27], an interactive applet allows students to resize, flip, move and rotate triangles to...
CK-12 Foundation
Ck 12: Exact Values for Inverse Sine, Cosine, and Tangent
[Free Registration/Login may be required to access all resource tools.] Find all angles on the unit circle matching exact trig ratios. Resource includes examples, videos, and practice problems.
Texas Instruments
Texas Instruments: Trig Ratios Exploring Sine, Cosine and Tangent
Using the Cabri Jr. App and the 83+/84+ calculators, students explore and calculate the various trig ratios. This is an easy construction but be sure to allow plenty of time for exploration and completion of the worksheet questions in...
Other
North Carolina Su: Triangles, Circles, and Waves (Oh My!)
This site has a basic overview of trigonometry focusing on the trig functions, trig ratios, and the unit circle.
Purple Math
Purplemath: Quadrants and Angles
Explains how to model angles in the x,y-plane, and demonstrates how to extend the concept of trig ratios to angles larger than 90 degrees.
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.
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...
Lawrence Hall of Science
The Math Page: Trigonometry
Concepts in Trigonometry are explained and illustrated here by a member of the math department at Borough of Manhattan Community College.
Khan Academy
Khan Academy: Trigonometric Ratios in Right Triangles
Learn how to find the sine, cosine, and tangent of angles in right triangles.
Interactive Mathematics
Interactive Mathematics: Trigonometric Functions
Just about everything you need to know about trigonometry can be found here. Interactive examples and demonstrations help to enhance the lessons. Although not required, the tutorial uses Live Math and Scientific Notebook.
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...
ClassFlow
Class Flow: Advanced Trigonometry
[Free Registration/Login Required] Students describe, analyze, and reason angles being as small or as large as they can imagine. Using trigonometrical ratios, this is a fun exercise in understanding how to examine the perfect graph.
Khan Academy
Khan Academy: Trigonometric Ratios in Right Triangles
Given the side lengths of a right triangle, find the sine, cosine, or tangent of one of the acute angles. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.