GeoGebra
  • Home
  • News Feed
  • Resources
  • Profile
  • People
  • Groups
  • App Downloads
About GeoGebra
Contact us: office@geogebra.org
Terms of Service – Privacy – License
Language: English

© 2018 GeoGebra

GeoGebra

Unit Circle: Complementary Angles

Author:
Brian Sterr
Topic:
Angles, Circle, Unit Circle
This sketch shows the relationship between an angle and its complement, . Drag around the circle and notice what happens to . How are the trigonometric ratios of the angles related?
GeoGebra Applet

1.

What is the geometric relationship between and ?

2.

The coordinates of are . From the relationship described in question 1, what are the coordinates of ?

3.

Since is a point on the unit circle corresponding to the angle in standard position, it has coordinates:

Therefore, for any angle , we have:

Related Topics

  • Congruence
  • Conic Sections
  • Constructions
  • Coordinates
  • Fractal Geometry

Discover Resources

  • Angle Pairs
  • SUPPORT VECTOR (3)
  • Hinge Theorem and Its Converse
  • feb 8
  • December Reflection

Discover Topics

  • Variance
  • Logarithm
  • Exponential Functions
  • Cylinder
  • Step Functions

GeoGebra

  • About
  • Team
  • News Feed
  • Partners

Apps

  • Graphing Calculator
  • Geometry
  • 3D Graphing
  • App Downloads

Resources

  • Classroom Resources
  • Groups
  • Tutorials
  • Help
  • Language: English
  • Terms of Service Privacy License
  • Facebook Twitter YouTube