Kemampuan Penalaran Matematis Siswa SMK dalam Memecahkan Masalah Barisan dan Deret Aritmatika

The learners must have reasoning ability. The level of mathematical reasoning ability of students plays an important role in solving mathematical problems, and the application of mathematics to everyday life. This study was conducted with the aim of describing the level of mathematical reasoning of class X SMK Graha Madina Singosari. The method used in this research is descriptive qualitative and the data collection procedure in this research is a written test. Students with low reasoning abilities show that they have not carried out a coherent problem solving process. They did not make any allegations regarding the problem at hand. Students with moderate abilities have carried out procedures coherently but not all questions have been answered correctly. The indicators achieved are making conjectures, carrying out mathematical manipulations and compiling evidence or reasons for the correctness of the solution. Meanwhile, students with high reasoning abilities fulfill all the predetermined indicators so as to reach the correct solution. However, students' mathematical reasoning abilities still need special attention in order to improve because only a third of students have high abilities