摘要:纵观古今,对于数学中对称思想方法的追求在一定程度上为科学研究指明了方向。对称思想方法,不仅在数学中具有重要的理论价值和实践价值,而且在各行各业中也具有广泛的应用价值,如建筑、艺术、医学、生物工程、装饰、陶瓷、壁画等等。所以,对学生而言,不论将来从事科学研究还是生产实践,一生受用无穷的,我认为当属对称思想方法。然而,在我们现行的《课标》(《九年制义务教育数学课程标准》和《数学课程标准》(高中版))中,关于对称思想方法,让学生了解多少,怎样掌握它,掌握到什么程度等,这些问题都没有被明确提出具体的要求。针对上述问题,笔者认为,对中学生而言,只要我们教者认真钻研教材,引导学生细心观察、系统总结,那么关于对称思想方法的掌握、应用就具备一定的可行性。本文正是以对称思想方法为主线,以中学数学教材为研究对象,应用教育学与心理学的相关理论知识,剖析蕴涵对称思想方法的知识点,挖掘其美的内涵,探究这些知识点的教学方法,研究学生的认知规律,让学生在欣赏数学美的同时,潜移默化地受到对称思想方法的熏陶,从而主动地运用对称的思想方法解答具有对称性的中学数学题,用对称的思想方法去思维,去学习其它科目,把数学作为自然科学的基础学科的功能,淋漓尽致地发挥出来。当然,对我们教育工作者而言,在日常的教育教学中,也可以应用对称思想方法来设计自己的教案。本文在最后一章给出了笔者在课堂教学中,应用对称思想方法的详细案例,充分体现了对称思想方法对课堂教学的影响。
本论文共分四章:
第一章,历史上的数学对称思想方法举例。主要以泰勒斯、赫尔曼•外尔、张奠宙等教授为代表,论述他们的对称思想在中学数学教材中的体现,分析《周易》的对称思想对中学数学的影响。
第二章,中学几何学中的对称。从平面图形的轴对称、中心对称和空间图形的面对称三方面展开论述。
第三章,中学代数学中的对称。以自然对数的来源为例,说明对称思想在选用对数底数时所起的关键性作用,依次展开论述函数中的对称思想、方程中的对称思想。
第四章,中学数学中对称思想的影响。主要从三方面论述对称思想的影响:首先,理论上图形变换中有对称思想;其次,课堂教学和问题解决中可应用对称思想,各学科中都能找到对称思想的影子;最后,潜移默化中对学生进行美育的熏陶。
关于中学数学中对称思想方法的研究意义,笔者认为关于对称性的考虑在一定程度上促进了数学的发展,如关于逆运算的考虑导致了数系的不断扩展,而且中学数学中的对称思想蕴涵着丰富的美学思想和思维方法,充分挖掘教材中的对称思想,具有重要的理论意义和现实意义,特别具有审美教育的价值。当然中学数学中的对称思想方法覆盖面广,还有待于我们进一步去研究。
关键词:中学数学对称思想方法,教学,变换
ABSTRACT :Making a general observation of all times, the pursuing for the symmetry thought in mathematics has indicated the direction to the scientific research in certain degree. The symmetry thought does not have an important value in theory and practice, but also plays an important role in various trades and occupations, for example, architecture, arts, medicine, bioengineering, decoration, china and painting so on. Therefore, as far as I am concerned, the symmetry thought will benefit students all their lives no matter that they will take up scientific research or produce practice in the future. But the present Course Standard (the Nine Year Compulsory Mathematics Course Standard and Mathematics Course Standard (for senior middle school)) doesn’t make a clear requirement on how much and what degree students should master it and how to master it. In view of the above questions, I think if only we, the teachers, study the teaching material carefully and guide students to observe carefully and summarize systematically, will the students master and use the symmetry thought well. This thesis uses the symmetry thought as a main clue and the mathematical teaching material as the object of study and it also uses the students’ cognition rules with the correspondent knowledge of psychology and pedagogies to analysis the knowledge spots which have symmetry thought and explore its beautiful connotation. The thesis also studies the teaching methodology of these knowledge spots. While students are appreciating the beauty of the mathematics, they will subtly and gradually receives the influence of symmetrical thinking method. Therefore, students will actively use the symmetrical thinking method to solve the mathematical problems in middle school, which involve the knowledge of symmetrical thinking method, and they will learn the other subjects with the symmetrical thought. The students will incisively displays the foundation function of mathematics to the natural sciences. What’s more, to us the teachers, we may use the symmetrical thought to design our teaching plans in our daily teaching and education. In the last chapter of this thesis, I provide detail examples, which have used the symmetrical thinking method, and they fully manifest the influence of symmetrical thinking method on the classroom instruction.
The thesis has four chapters:
The first chapter: Examples of Symmetrical Thinking Method in History. The examples are taken from the professors, such as Thales, Hermann Weyl, Zhang Dianzhou and Dai Qin. It discusses the embodying of the four scholars’ symmetrical thought in the middle school mathematical teaching material, and analyses the influence of symmetrical thought in Zhou Yi upon the middle school mathematics.
The second chapter: Symmetry in Middle School Geometry. It launches the elaboration from three aspects: flat surface artwork axial symmetry, centre symmetry and surface symmetry in space artwork.
The third chapter: Symmetry in Middle School Algebra. It takes the origin of logarithm as an example to illustrate the importance of symmetry thought when choosing the base number of logarithm and it takes turns to discusses the symmetry thought in function and equation.
The fourth chapter: the Influence of Symmetry Thought on the Mathematics of Middle School. It discusses the above topic from three aspects: First, the theoretical graph transformation has the symmetrical thought. Second, we can apply the symmetry thought to teaching and solving problems. The shadows of symmetry thought can be found in all subjects. Finally, it edifies the aesthetic education on the students in exerting a subtle influence on their thinking.
I think the meanings of studying the symmetry thought in middle school mathematics is that it pushes the development of the mathematical forward, e.g., the consideration of inverse operation leads to the expansion of the number system. Moreover in the middle school mathematics, symmetrical thought contains rich esthetics thoughts and thinking methods. Exploring deeply the symmetry thought in teaching materials has important theoretical and practical meanings and especially has the value of esthetic education. Of course, the symmetrical thinking method in middle school mathematics covers broad aspects, which is waiting for our further studies.
KEY WORDS: Symmetry Thought in Middlle School Mathematics, Teaching,Transformation
绪 论
随着社会的发展和中华民族的振兴,“科教兴国”越来越成为我国在新世纪谋求国家富强与民族振兴的重要战略。在这一重要战略背景下,深化教育改革,全面推进素质教育便成为教育改革与发展的主旋律。建国以来,我国先后进行了七次教育改革,每次改革都取得了明显成效。最近一次比较全面的教育改革是在《中华人民共和国义务教育法》颁布后,20世纪80年代后期至90年代初期,经过几年的努力,形成了我国基础教育课程的现行体系。尤其2001年《九年制义务教育数学课程标准》(以下简称《初中课标》)和2003年《数学课程标准》(高中版)(以下简称《高中课标》)的颁布,正是教育改革的重要体现。这两份纲领性文件明确提出数学教育的新理念:人人学有价值的数学,人人都能获得必需的数学,不同的人在数学上得到不同的发展。“人人学有价值的数学”是指作为教育内容的数学,应满足学生未来生活的需要,能适应学生个性发展的需求,并有益于启迪思维,开发智力;在更广泛的意义上,“有价值的数学”是满足素质教育的数学,它应当有助于学生健全人格的发展和积极向上价值观的形成,有助于学生自信心、责任感、合作意识、创新意识、求实态度和科学精神的培养。“有价值的数学”不仅是针对学生进一步学习有用的数学,而且是针对学生从事任何事业都有用的数学。