The purpose of this study is to describe the errors and causes that often occur in solving problems in the material building space beam and cube in terms of mathematical communication. In this study using a type of qualitative descriptive research, with data collection techniques used are tests, and interviews. The subjects of this study were 4th semester students at one of the universities in Bandung. The analysis technique used is an interactive technique which includes data collection, data reduction, data presentation, and conclusion drawing. The mathematical communication indicators used in this research are expressing everyday problems in mathematical languages / symbols, presenting allegations, and drawing conclusions. Errors made by students in solving problems are wrong in symbolizing data that is known and asked, does not calculate prerequisite data, determine formulas, and do not draw conclusions. The cause of the error is due to the assumption that symbolizing the known and asked data is not important, does not focus when working on the problem so that it is not thorough and understands the questions given, and the unfamiliarity to draw conclusions on each problem resolved

In the current era, education is not only focused on the academic teacher, but a teacher's personality is also very aware of. In realizing quality education, emotional intelligence can be used as an important thing to acquire knowledge for an educator to improve his quality as a teacher. The task of a math teacher is tough, a teacher must have a pedagogic and academic competence, personal competence and social competence. The competence of the four competencies kepribadianlah critical note, because most math teachers in Indonesia lacks emotional intelligence. This is caused by the material and metedologi given LPTK and teacher training institutions associated with personal competence remains low. If emotional intelligence is developed and trained math teachers well, the personality of the teacher will mature and are emotionally intelligent  that professionalism of    math teacher can be achieved. To that end, the math teacher is expected to have all the necessary competence, in order to achieve quality education and make the learning process successfully.ABSTRAK: Pada zaman sekarang, pendidikan tidak hanya terfokus kepada akademik seorang guru saja, namun kepribadian seorang guru pun sangat diperhatikan. Dalam mewujudkan pendidikan yang berkualitas, kecerdasan emosi dapat dijadikan satu hal yang penting untuk memperoleh ilmu pengetahuan bagi seorang pendidik untuk meningkatkan kualitasnya sebagai guru. Tugas seorang guru matematika memang berat, yaitu seorang guru harus mempunyai kompetensi pedagogik dan akademik, kompetensi kepribadian, serta kompetensi sosial. Dari keempat kompetensi tersebut kompetensi kepribadianlah yang sangat diperhatikan, karena sebagian guru matematika di Indonesia kurang memiliki kecerdasan emosional. Hal ini disebabkan oleh materi dan metedologi yang diberikan LPTK dan lembaga pembinaan guru yang terkait dengan kompetensi kepribadian masih terbilang rendah. Apabila kecerdasan emosional guru matematika dikembangkan dan terlatih dengan baik, maka kepribadian seorang guru tersebut akan matang dan memiliki emosi yang cerdas sehingga keprofesional guru matematika pun dapat dicapai. Untuk itu, guru matematika diharapkan mempunyai setiap kompetensi yang diperlukan, guna mewujudkan pendidikan yang berkualitas dan membuat proses belajar mengajar berhasil.