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ERIC Number: EJ1138738
Record Type: Journal
Publication Date: 2017
Pages: 12
Abstractor: As Provided
ISSN: ISSN-0020-739X
Relations among Five Radii of Circles in a Triangle, Its Sides and Other Segments
Sigler, Avi; Stupel, Moshe; Flores, Alfinio
International Journal of Mathematical Education in Science and Technology, v48 n5 p782-793 2017
Students use GeoGebra to explore the mathematical relations among different radii of circles in a triangle (circumcircle, incircle, excircles) and the sides and other segments in the triangle. The more formal mathematical development of the relations that follows the explorations is based on known geometrical properties, different formulas relating the radii to the sides and the inequalities between the different averages. The activities described were conducted with pre-service teachers of mathematics, with empirical investigation of the relations using dynamical geometry software, and formal presentation of proofs.
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Publication Type: Journal Articles; Reports - Descriptive
Education Level: Higher Education; Postsecondary Education
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Grant or Contract Numbers: N/A