33rd Conference of the International-Group-for-the-Psychology-of-Mathematics-Education, Thessaloniki, Yunanistan, 19 - 24 Temmuz 2009, cilt.1, ss.332
The purpose of this study is to determine preservice elementary mathematics teachers' proof performance on task-based interview questions. Individual interviews were conducted with 16 participants. It can be claimed that their performance was changed in terms of proof types, the most difficult one was proof by contradiction and the easiest type was found as direct proof.