@article{1913, author = "Silvanos Chirume and Victoria Ncube", abstract = "The use of Information and Communication Technologies (ICTs) in teaching and learning of subjects such as mathematics has been encouraged the world over. Among the available mathematical ICT software, Geogebra was chosen for this study. Geogebra is a free dynamic mathematical software which incorporates geometry, algebra and calculus features in one programme. The study, guided by the model-centred learning theory as well as the TPACK and Mathematical Knowledge for Teaching frameworks, sought to analyse a video lesson on transformations of trigonometrical functions to reveal the content knowledge, attitudes and behaviours of the teacher and learners as they interacted with Geogebra. Using systematic sampling, five out of 35 Advanced Level learners were selected. A volunteer research assistant then took a video of the teacher while she was using Geogebra to teach and illustrate, to the five leaners, the relationship between trigonometrical functions, their graphs and transformations. The research assistant also took a video of one of the learners illustrating and demonstrating, using Geogebra, the transformations of the trigonometrical functions. The study was carried out during COVID-19 lockdown period, hence the small sample size. To analyse data, the researchers watched the videos at least five times, looked for the number of times certain terms and concepts were mentioned or explained as well as the importance, usefulness or value attached to Geogebra and to the video lesson. Some emerging themes were then categorised. Findings of this study could help to shape the way videos and ICTs are perceived in model-centred and online mathematics learning which have recently become the norm.", issn = "23495219", journal = "IJIRES", keywords = "Mathematical Transformations, Trigonometrical Functions, Geogebra, Video Lesson, Video Analysis", month = "March", number = "2", pages = "71-81", title = "{M}athematical {T}ransformations using {G}eogebra: {A}n {A}nalysis of a {V}ideo {L}esson", volume = "9", year = "2022", }