The study constituted an investigation for concept images and mathematical reasoning of Grade 11 learners on the concepts of reflection, translation and stretch of functions. The aim was to gain awareness of any conceptions that learners have about these transformations. The researcher’s experience in high school and university mathematics teaching had laid a basis to establish the research problem. The subjects of the study were 96 Grade 11 mathematics learners from three conveniently sampled South African high schools. The non-return of consent forms by some learners and absenteeism during the days of writing by other learners, resulted in the subsequent reduction of the amount of respondents below the anticipated 100. The preliminary investigation, which had 30 learners, was successful in validating instruments and projecting how the main results would be like. A mixed method exploratory design was employed for the study, for it was to give in-depth results after combining two data collection methods; a written diagnostic test and recorded follow-up interviews. All the 96 participants wrote the test and 14 of them were interviewed. It was found that learners’ reasoning was more based on their concept images than on formal definitions. The most interesting were verbal concept images, some of which were very accurate, others incomplete and yet others exhibited misconceptions. There were a lot of inconsistencies in the students’ constructed definitions and incompetency in using graphical and symbolical representations of reflection, translation and stretch of functions. For example, some learners were misled by negative sign on a horizontal translation to the right to think that it was a horizontal translation to the left. Others mistook stretch for enlargement both verbally and contextually. The research recommends that teachers should use more than one method when teaching transformations of functions, e.g., practically-oriented and process-oriented instructions, with practical examples, to improve the images of the concepts that learners develop. Within their methodologies, teachers should make concerted effort to be aware of the diversity of ways in which their learners think of the actions and processes of reflecting, translating and stretching, the terms they use to describe them, and how they compare the original objects to images after transformations. They should build upon incomplete definitions, misconceptions and other inconsistencies to facilitate development of accurate conceptions more schematically connected to the empirical world. There is also a need for accurate assessments of successes and shortcomings that learners display in the quest to define and master mathematical concepts but taking cognisance of their limitations of language proficiency in English, which is not their first language. Teachers need to draw a clear line between the properties of stretch and enlargement, and emphasize the need to include the invariant line in the definition of stretch. To remove confusion around the effect of “–” sign, more practice and spiral testing of this knowledge could be done to constantly remind learners of that property. Lastly, teachers should find out how to use smartphones, i-phones, i-pods, tablets and other technological devices for teaching and learning, and utilize them fully to their own and the learners’ advantage in learning these and other concepts and skills / Mathematics Education / D.Phil. (Mathematics, Science and Technology Education)

The study constituted an investigation for concept images and mathematical reasoning of Grade 11 learners on the concepts of reflection, translation and stretch of functions. The aim was to gain awareness of any conceptions that learners have about these transformations. The researcher’s experience in high school and university mathematics teaching had laid a basis to establish the research problem. The subjects of the study were 96 Grade 11 mathematics learners from three conveniently sampled South African high schools. The non-return of consent forms by some learners and absenteeism during the days of writing by other learners, resulted in the subsequent reduction of the amount of respondents below the anticipated 100. The preliminary investigation, which had 30 learners, was successful in validating instruments and projecting how the main results would be like. A mixed method exploratory design was employed for the study, for it was to give in-depth results after combining two data collection methods; a written diagnostic test and recorded follow-up interviews. All the 96 participants wrote the test and 14 of them were interviewed. It was found that learners’ reasoning was more based on their concept images than on formal definitions. The most interesting were verbal concept images, some of which were very accurate, others incomplete and yet others exhibited misconceptions. There were a lot of inconsistencies in the students’ constructed definitions and incompetency in using graphical and symbolical representations of reflection, translation and stretch of functions. For example, some learners were misled by negative sign on a horizontal translation to the right to think that it was a horizontal translation to the left. Others mistook stretch for enlargement both verbally and contextually. The research recommends that teachers should use more than one method when teaching transformations of functions, e.g., practically-oriented and process-oriented instructions, with practical examples, to improve the images of the concepts that learners develop. Within their methodologies, teachers should make concerted effort to be aware of the diversity of ways in which their learners think of the actions and processes of reflecting, translating and stretching, the terms they use to describe them, and how they compare the original objects to images after transformations. They should build upon incomplete definitions, misconceptions and other inconsistencies to facilitate development of accurate conceptions more schematically connected to the empirical world. There is also a need for accurate assessments of successes and shortcomings that learners display in the quest to define and master mathematical concepts but taking cognisance of their limitations of language proficiency in English, which is not their first language. Teachers need to draw a clear line between the properties of stretch and enlargement, and emphasize the need to include the invariant line in the definition of stretch. To remove confusion around the effect of “–” sign, more practice and spiral testing of this knowledge could be done to constantly remind learners of that property. Lastly, teachers should find out how to use smartphones, i-phones, i-pods, tablets and other technological devices for teaching and learning, and utilize them fully to their own and the learners’ advantage in learning these and other concepts and skills / Mathematics Education / D.Phil. (Mathematics, Science and Technology Education)

Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-05-29T12:05:12Z No. of bitstreams: 1 valtercostafernandesjunior.pdf: 2769677 bytes, checksum: b4f02621c7dc7125c40dbf871a94503e (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-29T19:18:34Z (GMT) No. of bitstreams: 1 valtercostafernandesjunior.pdf: 2769677 bytes, checksum: b4f02621c7dc7125c40dbf871a94503e (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-29T19:19:04Z (GMT) No. of bitstreams: 1 valtercostafernandesjunior.pdf: 2769677 bytes, checksum: b4f02621c7dc7125c40dbf871a94503e (MD5) / Made available in DSpace on 2017-05-29T19:19:04Z (GMT). No. of bitstreams: 1 valtercostafernandesjunior.pdf: 2769677 bytes, checksum: b4f02621c7dc7125c40dbf871a94503e (MD5) Previous issue date: 2014-10-30 / Este trabalho introduz, primeiramente, uma reflexão a respeito da forma como a disciplina Análise vem sendo trabalhada há algum tempo. Para esta reflexão trazemos em nossa revisão de literatura pesquisas envolvendo o processo de ensino-aprendizagem nessa disciplina. Como referencial teórico adotado, apresentamos trabalhos sobre a teoria de Imagens de Conceito e Definição de Conceito que se encontram na linha de pesquisa do Pensamento Matemático Avançado. Conjuntamente, apresentaremos uma pesquisa de campo que teve como objetivo verificar e analisar as modificações nas imagens de conceito de alunos de um curso de Licenciatura em Matemática durante a aplicação de atividades de ensino sobre sequências de números reais, na perspectiva da disciplina Análise. Através de uma análise qualitativa, pudemos refletir sobre a aplicação das atividades de ensino - reflexão esta que leva em conta todo o processo e até mesmo a postura dos alunos frente às atividades. Outros pontos abordados neste trabalho foram as reações e impressões dos alunos ante a esta disciplina e o modo como eles lidam com a formalização dos conteúdos, que é o objetivo principal da mesma e o que a diferencia da disciplina de Cálculo. Nossa proposta teve como objetivo deixar os alunos pensarem nas questões e construírem os resultados, onde as intervenções feitas pelo pesquisador objetivavam orientá-los no processo de resolução ou em um momento extremo, para depois de já terem esgotado as discussões e orientações, apresentá-los o resultado. Desse modo, pretendemos explorar as várias representações que um objeto matemático pode assumir. Sendo assim, buscamos durante a realização das atividades sugerir e incentivar os mesmos a utilizarem as representações gráficas (reta numérica ou plano cartesiano), para que pudessem relacioná-las com as representações algébricas. Além do objetivo de relacionar as duas representações ditas acima, buscamos proporcionar um ambiente favorável ao entendimento das demonstrações formais, que normalmente é decorada pelos alunos. / This paper introduces a debate about the way the subject Analysis has been developed for some time now, using researches involving the teaching and learning process to make this discussion. Studies about the theory of Concept Imagens and Concept Definition, both found in the Advanced Mathematical Thinking line of research, will be used as theoretical background. A field work will be also presented, aiming to verify and analyze the changes in the concept images of Licentiateship in Mathematics students, during an application of teaching activities over sequences of real numbers, on the Analysis perspective. Through a qualitative analysis, a reflection on the implementation of educational activities could be performed, considering the whole process and even the attitude of students at facing the activities. Other points discussed in this study were the reactions and impressions of students when facing this subject and how they deal with the formalization of contents, which is perhaps the main purpose of it and what distincts Analysis from the Calculus subject. The principal proposal aimed is to let students think about the issues involved and build results on their own. The interventions made by the researcher intended to guide them in the resolution process or in an extreme point, after having already exhausted their discussions and orientations, to present them the results. Thus, we intend to explore the various representations that a mathematical object can take. Therefore, we seek during the realization of activities suggest to students and encourage them to use the graphical representations (number line or coordinate plane), so they could relate them to algebraic representations. In addition to this previous objective, we strive to provide a favorable environment for the understanding of formal statements, which is usually memorized by the students.