The Validity of Hypothetical Learning Trajectory Based on Realistic Mathematic Education on Function Topics for Grade X Senior High School

The tendency of teachers to teach functions mechanistically causes several problems in learning. Students are less interested and less motivated in learning mathematics, especially for the function topic. This study discusses the validity of the hypothetical learning trajectory on the topic of the function of grade X in Senior High School. The development model was the Plomp model, but in this study it was only up to the preliminary research stage. Based on the results of interviews with mathematics teachers at Senior High School4 and Senior High School 11 in Solok Selatan, it can be concluded that in the learning process, teachers only relied on textbooks, so that learning was less effective and the material in the textbook was still non conceptual and less related to the real world of students so that students found it difficult to understand the material but rather to memorize the material.