Analysis Error Student in Solving Problem Logarithm Based on the Kastolan Procedure

Mathematics is very important in teaching students to have and apply mathematical thinking patterns in everyday life and become a reference for studying various other branches of science. One of the mathematics materials is logarithms, where students often make mistakes when solving these problems, so it can indicate how far students have mastered the logarithm material chosen for this research because logarithms have properties that students must understand. So, this research aims to analyze the errors made by students when solving logarithm problems using the Kastolan procedure. Subject in this study, nine students from class X IT SMKS, Darel Hikmah Pekanbaru. The research instrument used a 5-item logarithmic description test instrument. The data analysis techniques are data reduction, data presentation, and conclusion. Based on the research data results, it was concluded that students made conceptual errors, namely the inability to apply the concept of the properties used. Procedural errors were when students were unable to solve the problem until they got the final solution, and technical errors occurred because they made mistakes in calculations to produce answers wrong.