Lawrence Hall of Science
The Math Page: Trigonometry: The 30 60 90 Right Triangle
Here is a site that clearly and thoroughly explains the trigonometry of the 30-60-90 right triangle. There are example problems solved, problems for the student to attempt, and answers to the student problems. Point this site out to...
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.
Curated OER
Zona Land: Trigonometry, Right Triangles
This site provides information on sine, cosine, and tangent. Lengths of the sides are discussed and many diagrams/tables are shown.
Lawrence Hall of Science
The Math Page: Trigonometry: Trig Functions of an Acute Angle
Here is a site that clearly and thoroughly explains the trigonometric functions of acute angles within a right triangle. There are example problems solved, problems for the student to attempt, and answers to the student problems. Point...
Khan Academy
Khan Academy: Right Triangle Trigonometry Review
Review right triangle trigonometry and how to use it to solve problems.
Math Open Reference
Math Open Reference: Tangent (Tan) Function: Trigonometry
Learn about the tangent with this helpful reference tool. Provides a detailed definition, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
Math Open Reference
Math Open Reference: Sine (Sin) Function Trigonometry
A complete reference guide to the sine function. It provides definitions, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
Math Open Reference
Math Open Reference: Cosecant (Csc) Trigonometry Function
Learn about the trigonometric function, cosecant, with this helpful reference tool. Provides a detailed definition and examples that enhances further explanation.
CK-12 Foundation
Ck 12: Geometry: Laws of Sines and Cosines
[Free Registration/Login may be required to access all resource tools.] This concept teaches students to find missing sides and angles in non-right triangles using the Laws of Sines and Cosines.