Abstract
This descriptive qualitative research aims to describe the form of mathematical representation that arises when students understand the relationship between changes in the coefficient of trigonometric functions with their graphical functions through GeoGebra media. Students in a class of 30 students are selected as research subjects and given a Student Worksheet. From the results of the student's work, it can be seen that there are 3 types of the tendency of representation that are used by students to complete Worksheets. Of the 3 types of trends, each student is taken 1 person who will further discuss the results of his work randomly because it is considered to represent the work of other students. The results showed that students represented Geogebra's appearance in 3 forms namely verbal representation, mathematical expression representation, and visual representation.