The understanding of the triangle in Lobachevski geometry through local culture

Abstract

A triangle is an abstract object in Lobachevsky’s Geometry. The local content is needed as a starting point for learning geometry. This study aims to describe student’s understanding of triangles in Lobachevsky Geometry through local culture. This is an exploratory study. The focus is on analyzing the needs of student’s ability to understand the properties of Lobachevsky’s geometry. The subjects of this study were mathematics education students in Bengkulu, Indonesia. In-depth interviews are based on assignments about triangular problems. The problem is taken from the culture of Bengkulu society about “glutinous rice cake”. Data were analyzed through a collection of interviews and other physical activity. The results of this study are the subjects can connect the elements together to form a coherent unity based on observations of sticky rice cake. They produced a new product by organizing several elements into different forms or patterns from before, namely triangles with a large number of angles of less than 180. The conclusion of this study is that student’s understanding of triangles in Lobachevsky Geometry has reached the level of creating a new proposition, namely the number of angles in triangles in Lobachevski Geometry is less than 180.