Exploration the conception of prospective students teacher about limit of function

The purpose of this research is to explore the conception of prospective students teacher that highly skilled on mathematical ability about limit function, especially in the aspects of understanding, representation, mental image and proposition. This study was conducted by a qualitative exploratory method. The subject was one of the students in the mathematics education of Syiahkuala University which being chosen according to the expected criteria.. The research instrument was divided into main and supporting instrument. The data was analyzed by reducing, presenting, interpreting and concluding. The analyzing data results obtained the subject’s conception about limit function were elaborated the meaning of limit function with representation verbal, graphic, symbol, and logical explanation, expressing the limit function definition with verbal representation, graphic, table and symbol. The subject defined the correlation of limit function by imaging, revealing, and using one-sided the limit of function. They expanded the propositions by symbols, explained logically, and proved using a formal definition.