  The formal definition of limit is one mathematical idea that gives
difficulties to most students. Therefore, it is necessary to provide engaging
activity in order to construct the students' understanding about the
definition. This study aims to shed light on designing activities with dynamic
geometry software to facilitate the students in discovering the formal
definition of limit. Forty-eight students participated in the study. Both
quantitative and qualitative data were collected from the students' responses
in and attitudes toward the activities. The students' responses were gathered
directly by using the dynamic geometry software whereas an online questionnaire
was used to collect the students' attitudes. The results of the study then
presented in this paper. Further, a set of suggestions in designing and
implementing dynamic geometry environments to foster students' understanding
about formal definition of limit was also proposed.
