• Journal of the Korean School Mathematics Society
• /
• v.12 no.4
• /
• pp.365-388
• /
• 2009

In this paper we solve various triangle construction problems given by three points(a midpoint of side and other two points). We investigate relation between these construction problems, draw out a base problem, and make hierarchy of solved construction problems. In detail we describe analysis for searching solving method, and construction procedure of required triangle.

• Communications of Mathematical Education
• /
• v.9
• /
• pp.153-164
• /
• 1999

작도 문제는 역사적으로 아주 오래된 문제 중의 하나일 뿐만 아니라, 현재 우리 나라 기하 교육에 있어 매우 중요한 역할을 하고 있다. 즉, 평면 기하의 중심 정리들 중의 하나인 삼각형의 합동 조건들을 도입하기 위한 기초로 주어진 조건들(세 선분, 두 선분과 이들 사이의 끼인각, 한 선분과 그 양 끝에 놓인 두 각)에 상응하는 삼각형의 작도가 행해진다. 그러나, 현행 수학 교과서나 수학 교수법을 살펴보면, 작도 문제 해결 방법 및 지도에 대한 연구가 미미한 실정이다. 본 연구에서는 작도 문제의 특성, 작도 문제의 해결 방법 및 지도에 관한 접근을 모색할 것이다. 이를 통해, 학습자들이 다양한 탐색 활동 속에서 작도 문제를 탐구할 수 있는 이론적, 실제적 근거를 제시하고, 수학 심화 학습에 작도 문제를 이용할 수 있는 가능성을 제시할 것이다.

• Journal of the Korean School Mathematics Society
• /
• v.11 no.3
• /
• pp.399-420
• /
• 2008

In this paper we solve various triangle construction problems related with radius of escribed circle using algebraic method. We describe essentials and meaning of algebraic method solving construction problems. And we search relation between triangle construction problems, draw out 3 base problems, and make hierarchy of solved triangle construction problems. These construction problems will be used for creative mathematical investigation in gifted education.

• Journal of Educational Research in Mathematics
• /
• v.27 no.1
• /
• pp.51-67
• /
• 2017

Analogical reasoning is a mathematically useful way of thinking. By analogy reasoning, students can improve problem solving, inductive reasoning, heuristic methods and creativity. The purpose of this study is to analyze the analogical reasoning of preservice mathematics teachers while constructing quadratic curves defined by eccentricity. To do this, we produced tasks and 28 preservice mathematics teachers solved. The result findings are as follows. First, students could not solve a target problem because of the absence of the mathematical knowledge of the base problem. Second, although student could solve a base problem, students could not solve a target problem because of the absence of the mathematical knowledge of the target problem which corresponded the mathematical knowledge of the base problem. Third, the various solutions of the base problem helped the students solve the target problem. Fourth, students used an algebraic method to construct a quadratic curve. Fifth, the analysis method and potential similarity helped the students solve the target problem.

• Communications of Mathematical Education
• /
• v.30 no.4
• /
• pp.469-497
• /
• 2016

In this research, we develop a systematic learning the materials on constructibility of cubic roots. We propose two sets of materials: one is based on concepts of field, vector space, minimal polynomial in abstract algebra, another based on properties of cubic roots in elementary algebra. We assess the validity, applicability, defects and merits of developed materials through prospective teachers, in-service teachers, and professionals. It could be expected that materials be used for advanced secondary students, mathematics majoring college students and mathematics teachers. Furthermore, we may expect the materials be useful for understanding and solving the (un)constructibility problems.

• Journal for History of Mathematics
• /
• v.22 no.2
• /
• pp.99-116
• /
• 2009

In this paper we study errors related with constructing regular polygons in the book 'Method of Ruler and Compass' written three hundreds years ago. It is well known that regular heptagon and regular nonagon are not constructible using compass and ruler. But in this book construction methods of these regular polygons is suggested. We show that the construction methods are incorrect, it include some errors.

• School Mathematics
• /
• v.4 no.4
• /
• pp.601-615
• /
• 2002

This paper analyzed <7-나> and <8-나> textbooks and teacher instruction activities in classrooms, focusing on procedures used to solve construction problems. The analysis of the teachers' instruction and organization of the construction unit in <7-나> textbooks showed that the majority of the textbooks focused on the second step, i.e., the constructive step. Of the four steps for solving construction problems, teachers placed the most emphasis on the constructive order. The result of the analysis of <8-나> textbooks showed that a large number of textbooks explained the meaning of theorems that were to be proved, and that teachers demonstrated new terms by using a paper-folding activities, but there were no textbooks that tried to prove theorems through the process of construction. Here are two alternative suggestions for teaching strategies related to the construction step, a crucial means of connecting intuitive geometry with formal geometry. First, it is necessary to teach the four steps for solving construction problems in a practical manner and to divide instruction time evenly among the <7-나> textbooks' construction units. The four steps are analysis, construction, verification, and reflection. Second, it is necessary to understand the nature of geometrical figures involved before proving the problems and introducing the construction part as a tool for conjecture upon theorems used in <8-나> textbooks' demonstrative geometry units.

• Education of Primary School Mathematics
• /
• v.17 no.2
• /
• pp.127-157
• /
• 2014

The purpose of the study is to enhance the figure analysis ability for pre-service elementary teacher by using GSP. To do this, we limited to teaching competence divide into ability various problem-solving, extract key elements, predict the difficulty of student and investigated the initial of them, the reality of GSP construction. As results, pre-service elementary teachers made errors, proposed teaching focused on the character using in the problem solving, and found that in one particular difficulties to find the students. The reality of GSP construction activity was possible to explore through the partially constructed a number of various properties, but we found to have difficulty in the connection between concepts. and integrated view of the problem analysis. After visual identification and exploration through the GSP construction, problem-solving ability became a little more variety and changed their direction in order to focus the student's anticipated difficulties. From these results, we could extract some pedagogical implications helping pre-service teachers to reinforce teaching competence by GSP construction.

• Journal for History of Mathematics
• /
• v.21 no.2
• /
• pp.119-134
• /
• 2008

In this paper we study a book 'Method of Ruler and Compass' written in Russia three hundreds years ago. In this book many construction problems related with plane figures and solid figures are solved. In this study we analyze construction method of some regular polygon(square, regular pentagon, regular octagon, regular decagon) suggested in 'Method of Ruler and Compass', give mathematical proofs of these construction.

• Korean Journal of Crystallography
• /
• v.12 no.1
• /
• pp.31-36
• /
• 2001

결정학의 핵심 과제는 위상(phase) 문제의 해결이다. 이 위상 묹를 해결하는 한 방법으로 요즘의 고속 컴퓨터를 사용하는 시행착오법(trial and error method)을 가상해 볼 수 있다. 간단한 예를 들면, centrosymmetric인 삼사정계(triclinic system)에 속한 비교적 작은 유기화합물인 경우, 전형적으로 3000개 정도의 회절 강도가 측정된다. Centrosymmetric 공간군(space group)의 구조 인자(structure factor)는 위상이 0°이거나 180°이기 때문에, 구조 인자는 "+"이거나 "-"부호를 가지므로 3000개 각각에 두 가지 부호를 배당할 수 있다. 이 3000개의 부호를 조합할 수 있는 개수는 2/sup 3000/개로 이 개수만큼의 Fourier 지도들을 작도하면 그 중의 하나는 옳은 것이다. Fourier 지도 한 개를 작도하는데 1분이 소요된다고 가정하면, 이들을 모두 계산하는데 2/sup 2981/년의 계산 시간이 소요된다. (참고로 2/sup 10/=1084). 따라서 시행착오법으로는 도저히 불가능함을 알 수 있다. 더구나, noncentrosymmetricc 공간군에서는 더욱 어렵게 된다. 그리하여 위상 문제를 해결하려는 많은 시도가 행해졌는데, 그것들 중의 하나가 Patterson 방법이다.