Activity
Texas Instruments

Texas Instruments: Geometric Representation of Trig Functions

For Teachers 9th - 10th Standards
Using similar triangles, a relationship is established between the six trigonometric functions of an angle and simple line segments. These relationships are then confirmed using line segment measurement capabilities of the graphing...
Handout
Purple Math

Purplemath: Basic Trigonometric Ratios: Examples

For Students 9th - 10th Standards
Demonstrates how to use trig ratios to do simple solving of triangles.
Handout
Purple Math

Purplemath: Special Angle Values: 30 60 90 and 45 45 90 Triangles

For Students 9th - 10th
Explains a simple pictorial way to remember basic reference angle values. Provides other memory aids for the values of trigonometric ratios for these "special" angle values, based on 30-60-90 triangles and 45-45-90 triangles.
Website
Other

Dan Sloughter: Trigonometric Series Approximations

For Teachers 9th - 10th
Understand how trigonometric functions can model periodic behavior. See the application of periodic behavior, amplitude, frequency in sound waves. Make sure to turn up your sound to load an audio file to play the given tone of the...
Handout
Northeast Parallel Architectures Center, Syracuse University

Npac Reu Program: Conversion

For Students 9th - 10th
This site displays the formulas for the simple conversions of degrees to radians and radians to degrees. Near the bottom of the page there are examples of these conversions.