Abstract
This study investigates pre-service mathematics teachers’ concept images of radian and possible sources of such images. A multiple-case study was conducted for this study. Forty-two pre-service mathematics teachers completed a questionnaire, which aims to assess their understanding of radian. Six of them were selected for individual interviews on the basis of theoretical sampling. The data indicated that participants’ concept images of radian were dominated by their concept images of degree. As the data in this study suggested, pre-service mathematics teachers were reluctant to accept trigonometric functions with the inputs of real numbers but rather they use value in degrees. More interestingly, they have two distinct images of π : π as an angle in radian and π as an irrational number.
Acknowledgements
This article is a full version of Topcu et al. Citation9 presented in the International Conference on the Psychology of Mathematics Education focusing on different subjects. I would like to acknowledge and express my appreciation to the graduate students who were the co-authors of Topcu et al. Citation9, Mahmut Kertil, Kamil Yılmaz, Tahsin Topçu and Osman Önder, for their assistance in conducting the questionnaire that was used in this study and helping with the interview transcripts.
Notes
Note
1. Note that some of the points are not given as (x, f(x)), therefore the ordinate does not depend on the abscissa for these points.