An investigation of secondary mathematics teachers' perception and conceptualization of the notion of "Undefined"

This research aims to identify the coding of undefined made by the secondary school mathematics teachers and to clarify how they conceptualize the various types. There search method is focused group interview which is already a type of qualitative type. In this method, the aim is not to define codes but understand, not to generalize but to clarify the variety, not to make descriptions about a subjects but to find out how they concept (Kreuger, 1994). The coordinating of the focused group interview is realized by a field expert who is a lecturer of Gaziantep University and the supervisor of this study at the same time. The data is gathered by analyzing the expressions made by the subject teachers. In the analysis, the codes made for the undefined are coded taking the subjects definitions for the various undefined types. These codes are converted to findings after designing to their categories and the similarities and shown as figures.As a result of the research, it is found out that the subjects made different definitions to undefined change to context and then conceptualized them differently.