Analyze Math
Analyze Math: Special Triangles Used in Trigonometry
The trigonometry tutorial investigates special triangles. The activity includes isosceles right triangles and 30-60-90 triangles. The examples show how to obtain the six trigonometric ratios of the special angles using special triangles.
Discovery Education
Discovery Education: Web Math: Calculate a Right Triangle
WebMath offers a java applet that allows you to input information about a right triangle, and then solves the triangle for any of the missing pieces of information. It also gives a detailed solution using the information that you provided.
Khan Academy
Khan Academy: Solve for a Side in Right Triangles
Given one side length and an acute angle in a right triangle, find another side using trigonometry. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Solve for a Side in Right Triangles
Given one side length and an acute angle in a right triangle, find another side using trigonometry.
Government of Alberta
Learn Alberta: Math Interactives: Exploring Trig Ratios
Investigate the cosine, sine, and tangent ratios of trigonometry using this interactive Learn Alberta math resource. Students will use these ratios to determine a right triangle's unknown side or angle. Be sure to follow the link to the...
Mathigon
Mathigon: Geometry: Triangles and Trigonometry: Properties of Triangles
This lesson focuses on the properties of triangles, a closed shape that has three sides, three vertices, and and three internal angles. There are different types of triangles such as a right triangle, obtuse, and acute based on the...
TeachEngineering
Teach Engineering: Trigonometry via Mobile Device
Students investigate the relationships between angles and side lengths in right triangles with the help of materials found in the classroom and a mobile device.
TeachEngineering
Teach Engineering: Handheld Trigonometry
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.
CK-12 Foundation
Ck 12: Trigonometry: Pythagorean Theorem for Solving Right Triangles
[Free Registration/Login may be required to access all resource tools.] Finding unknown sides in a triangle using other sides and angles.
Mangahigh
Mangahigh: Shape: 3 D Trigonometry
Test your knowledge of determing the lengths and angles of right triangles.
Texas Instruments
Texas Instruments: Sin, Cos, and Tan of Right Triangles
In this activity, students explore a right angled triangle and its trigonometric concepts. They investigate the trigonometric ratios for the angles of the triangle.
Varsity Tutors
Varsity Tutors: Hotmath: Graphing Calculator Practice: Right Triangles and Trigonometry
Practice using your graphing calculator for solving right triangle trigonometry and non-right triangle trigonometry. If you get stumped or if you would like to check your work, then select the View Solution button, which is located...
CK-12 Foundation
Ck 12: Trigonometry: Sine, Cosine, and Tangent Functions
[Free Registration/Login may be required to access all resource tools.] Calculate sine, cosine, and tangent functions using the sides of a right triangle.
CK-12 Foundation
Ck 12: Trigonometry: Angles of Elevation and Depression
[Free Registration/Login may be required to access all resource tools.] Find distance using right triangles and angles of elevation or depression.
CK-12 Foundation
Ck 12: Trigonometry:lengths of Triangle Sides Using the Pythagorean
[Free Registration/Login may be required to access all resource tools.] Find the length of sides of right triangles using the Pythagorean Theorem.
Curated OER
Trigonometry Realms
Excellent site reviewing the realms of Trigonometry. Topics Include the trig functions, graphs, right triangles and much more.
TeachEngineering
Teach Engineering: Trig River
Students learn about and use a right triangle to determine the width of a "pretend" river. Working in teams, they estimate of the width of the river, measure it and compare their results with classmates.
Oswego City School District
Regents Exam Prep Center: Area of a Triangle and Parallelogram Using Trig
How can trigonometry be used to find the area of a triangle or parallelogram? Does the triangle need to be a right triangle, and how accurate can the results possibly be? The answers to these questions are found here along with several...
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.
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.
TeachEngineering
Teach Engineering: You've Got Triangles!
Students learn about trigonometry, geometry and measurements while participating in a hands-on interaction with LEGO MINDSTORMS NXT technology. First they review fundamental geometrical and trigonometric concepts. Then, they estimate the...
Math Open Reference
Math Open Reference: Cosine (Cos) Function Trigonometry
A complete reference guide to the cosine function in trigonometry. It provides definitions, examples, and an interactive activity that enhances further explanation.
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...
CK-12 Foundation
Ck 12: Trigonometry: Pythagorean Theorem for Solving Right Triangles
[Free Registration/Login may be required to access all resource tools.] This lesson applies the trigonometric ratios and their inverses to real-life situations.