Sugi Hartono, Tatag Yuli Eko Siswono, Rooselyna Ekawati
This research aims to describe preservice teachers' concept image in proving the Pythagorean Theorem. This research is a qualitative research with 105 preservice mathematics teachers' at Surabaya State University. Data was collected by means of interviews and tests, then analyzed using the Miyazaki classification: Proof A and B are deductive proof and Proof C and D are inductive proof. The research study found that 21% of preservice teachers successfully answered the proof questions, while 79% struggled with proving. The research highlighted three key challenges related to inadequate concept images: a lack of mathematical language (CI1) in Proof B and Proof C, difficulty in organizing individual steps (CI2) in Proof B, Proof C, and Proof D, and the inability to articulate logical structures (CI3) in Proof D. © 2025 Author(s).
Universitas Negeri Surabaya, Jl. Ketintang, Ketintang, Kec. Gayungan, Jawa Timur, Surabaya, 60231, Indonesia
