[Free Registration/Login may be required to access all resource tools.] This lesson covers using the Law of Cosines to find an angle in a triangle.

Features a definition, examples, and a video lesson all related to angles. [0:35]

Learn about angles with this helpful reference tool. Provides a detailed definition, examples, and an interactive activity that enhances further explanation. Includes links to related topics.

Learn about arc length with this handy reference guide. Provides a detailed definition examples, and an interactive activity that enhances further explanation. Includes links to related topics.

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

A complete look at trig functions. From an "overview," page giving general definitions and important vocab words, to a listing of the 12 trig functions, to an explanation of the three modes used in trigonometry, to the procedures of how...

Use these interactive activities as a supplementary material to visualize some basic concept of Trigonometry.

This applet allows the user to create the graphs of sin, cos, and tan by moving a scroll bar. The user can watch the unit circle and the graph simultaneously to see how the two are related. The user may also choose to see the angle...

Explains formulas for areas of sectors of circles and lengths of arcs. Demonstrates how to use the formulas in each of degrees and radians.

This site offers a picture and short discussion of a sector of a circle. The site contains a link to the area of a sector of a circle in both degrees and radians. There are links to related words.