Analyzing graphs of functions and their transformations

Abstract

A subject that is frequently discussed deals with the behavior of the graphs of real functions, when the values of the parameters inserted in the composition of their equations are varied. This workshop intends, with the aid of the computer, to observe some transformations that occurred in the graphs of several real functions when it is added, subtracted, multiplied or divided by a real constant, the dependents and independent variables of those functions. To observe such transformations, we used the freeware Winplot, offered free in the internet in the site http://math.exeter.edu/rparris. The use of the computer makes it possible to draw the graphs of the functions quicker. The student’s interaction with the computer/software allows him to formulate his conjectures and verify them in a dynamic way. This software was chosen because of the easiness in the handling of her graphic interface since it possesses interesting tools that facilitate the understanding of the explored mathematical concepts. One ofthose tools allows the student to make animations in the graphs of the functions by just varying the values of the parameters inserted previously in their equations and, doing so, to identify a pattern for the transformations. Another advantage is that this software is found in several languages, including Portuguese. With all the technological progress that we have witnessed, it is important that the teachers-to-behave contact with new technologies and their applications.