Mathematical Justification Ability: Students' Divergent and Convergent Process in Justifying Quadrilateral

摘要

Justification is an important component in learning mathematics to optimize reasoning skill, understanding concepts and mathematical communication. This research is qualitative descriptive research because it aims to obtain a natural picture of the student's mathematical justification on the quadrilateral material. The subjects of this study consists of two students who have different learning style that are divergent and convergent. Data collection was done by giving related statements about quadrilateral material and used semi-structured questionnaire to justify their statement. Data was analysed based on mathematical justification indicator that were recognition, building-with, awareness. Based on the research result, the subject of divergent and convergent showed differences, those were not so far in the process of mathematical justification. The divergent subject analysed the mathematical situation through the form of a rule based on the apparent (concrete) information, but the convergent subject considered how the previous rule was formulated to search for new rules. It showed that in the learning process, justification could provide a picture of the students' thinking flow and explanation of the truth of a statement.