Sine and Cosine of Complementary Angles and Special Angles

Building trigonometric basics here will last a mathematical lifetime. Learners expand on the previous lesson in a 36-part series by examining relationships between the sine and cosine of complementary angles. They also review the ratios of the special angles and learn patterns to help remember these ratios.

12 Views 7 Downloads
CCSS: Designed
Instructional Ideas

  • Use an applet or create a geogebra demonstration to illustrate example #2
  • Create a set of 30-60-90 triangles with known side length; the ratios of sides should become known values
Classroom Considerations

  • Some of the symbols may be confusing for pupils; substitute actual values for angles and/or side lengths

  • Emphasizes the ratios for 30-, 60-, 45-, and 90-degree angles
  • Includes a teacher guide with suggestions for differentiation 

  • None