Analysis of Mathematics Education Students’ Errors in Solving Monotonic Sequence Problems Using Newman’s Taxonomy

The purpose of this study is to examine the types of errors made by students of the Mathematics Education Study Program at the State University of Medan when attempting to solve monotonic sequence problems in the Real Analysis course. This study employs a qualitative descriptive methodology using the Newman Taxonomy approach, which categorizes errors into five types: reading, comprehension, transformation, process skills, and writing final answers. The data collection technique involved distributing essay questions online through Google Forms to selected students. Five students who had completed the monotonic sequence material were given a written test consisting of essay questions. The data were then analyzed using data reduction, data presentation, and conclusion-drawing techniques. The analysis revealed that the most common errors made by students were in process skills and final answer writing. Errors in writing final answers occurred when students failed to use correct notations or symbols in their solutions, despite understanding the subject matter and procedures. Process skill errors stemmed from difficulties in algebraic manipulation and the application of proof techniques. These errors were caused by a limited understanding of the concept of monotonic sequences and weaknesses in applying the steps of mathematical proofs. The findings highlight the need for instructional approaches that emphasize conceptual understanding and the systematic application of analytical thinking.