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...
Windstream
Ojk's Precalculus Study Page: Evaluating and Graphing Sine and Cosine
An introduction to graphing the sine and cosine functions by using the 30-60-90 and 45-45-90 right triangle values of the two functions as guides.