A Fuady¹ , Purwanto² , B E Irawan² , S Rahardjo²

¹ Mathematics Education Program, Postgraduate Program, Universitas Negeri Malang, Jl. Semarang, Malang 65145, Indonesia

² Mathematics Education Program, Postgraduate Program, Universitas Negeri Malang, Jl. Semarang, Malang 65145, Indonesia

E-mail : fuadyanies@gmail.com

This research purposed to describe the students with reflective and cognitive style in solving composition function. This research used qualitative research methods. The data was collected by written test and task-based interviews. The subject consisted of two students  Islamic University of Malang  that were measured by MFFT (Mathcing Familiar Figures Test). The data were analyzed based on the four main reflective abstraction, that is interiorization, coordination, encapsulation and generalization. This result showed that subject with reflective cognitive style in solving function composition problems met all components of reflective abstraction ( interiorization; subject observes the relationship of the origin region of the first function and the second functional region, coordination; compute the function of L and G, encapsulation ; set the formula G (x) with the new variable t, generalization; set the formula L (x) and determine the function L). While subject with impulsive cognitive style in solving function composition problem met three components of reflective abstraction (interiorization; observe and try to read back the problem, coordination; compute the function of F and M, generalization; set F ₒ M). The result of this research can also as a guideline in the future assessment reflective abstraction based on cognitive style