Abstract
This study explored the utilisation of GeoGebra as a modelling tool to develop undergraduate
engineering mathematics students’ conceptual and procedural knowledge of complex
numbers. This mission was accomplished by implementing GeoGebra-enriched activities,
which provided carefully designed representational support to mediate between students’
initially developed conceptual and procedural knowledge gains. The rectangular and polar
forms of the complex number were connected and merged using GeoGebra’s computer
algebra systems and dynamic geometric systems platforms. Despite the centrality of complex
numbers to the undergraduate mathematics curriculum, students tend to experience
conceptual and procedural obstacles in mathematics-dependent physics engineering topics
such as mechanical vector analysis and electric-circuit theory. The study adopted an
exploratory sequential mixed methods design and involved purposively selected first-year
engineering mathematics students at a South African university. The constructivist approach
and Realistic Mathematical Education underpinned the empirical investigation. Data were
collected from students’ scripts. Implementing GeoGebra-enriched activities and providing
carefully designed representational support sought to enhance students’ conceptual and
procedural knowledge of complex numbers and problem representational competence. The
intervention additionally helped students to conceptualise and visualise a complex rectangular
number. Implications for technology-enhanced pedagogy are discussed.
Contribution: The article provides exploratory insights into the development of undergraduate
engineering mathematics students’ conceptual and procedural knowledge of complex numbers
using GeoGebra as a dynamic digital tool. Key findings from the study demonstrated that
GeoGebra appears to be an effective modelling tool that can be harnessed to demystify the
complexity of mathematics students’ conceptual and procedural knowledge of complex numbers.