STUDENTS’ VISUAL REASONING OF THE CONNECTION BETWEEN FUNCTION AND ITS DERIVATIVE : A GRAPHICAL APPROACH (39 - 48)
The study described in this article is part of a larger project, in which we track the development of students’ visual reasoning when solving derivative problems using graphs. Students’ difficulties in understanding derivatives and further to relate to their original functions have been well acknowledged. We engaged 194 pre-university students with tasks measuring their ability to connect graphs of derivative and properties of functions and analyzed their solution methods. Finding shows that students employed both graphical (using sign diagram and sketching the original function) and algebraic methods. Implication of instructions are discussed.