Investigating rates of change in volume without calculation leads to an enriched sense of the optimization process and encourages reflection and connection among different approaches.
Walter J. Whiteley, firstname.lastname@example.org, is professor of mathematics and statistics at York University in Toronto and a member of the Faculty of the Graduate Program in Education. His research interests are discrete applied geometry and geometry education.
Ami Mamolo, AMamolo@edu.yorku.ca, is an assistant professor in the Faculty of Education at York University. Her interests include university students' learning and understanding of mathematics.