Reflex Angle

Pronunciation: /ˈri.flɛks ˈæŋ.gəl/ Explain

 Click on the blue point and drag it to change the figure. Can you find all 5 angle classes represented? Manipulative 1 - Angle Classes Created with GeoGebra.

Angles are divided into four classes according to their measure. A reflex angle is an angle that measures more than 1/2 of a full circle and less than afull circle.

Classes of Angles
α < 90° α < π/2 rad. Acute angle
α = 90° α = π/2 rad. Right angle
90° < α < 180° π / 2 < α < π rad. Obtuse angle
α = 180° α = π rad. Straight angle
180 < α < 360° π < α < 2π rad. Reflex angle
α = 360° α = 2π rad. Full angle
Table 1: Classes of angles

References

1. McAdams, David E.. All Math Words Dictionary, reflex angle. 2nd Classroom edition 20150108-4799968. pg 153. Life is a Story Problem LLC. January 8, 2015. Buy the book
2. reflex angle. merriam-webster.com. Encyclopedia Britannica. Merriam-Webster. Last Accessed 12/4/2018. http://www.merriam-webster.com/dictionary/reflex angle. Buy the book

McAdams, David E. Reflex Angle. 5/2/2019. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/r/reflexangle.html.

Revision History

5/2/2019: Changed equations and expressions to new format. (McAdams, David E.)
12/21/2018: Reviewed and corrected IPA pronunication. (McAdams, David E.)