Extrema points: concept images, mis-in and mis-out examples

Abstract

This paper reports on students’ conceptions of minima points. Written assignments and individual interviews uncovered salient, concept images, as well as erroneous mis-out examples that mistakenly regard examples as non-examples and mis-in examples that mistakenly grant non-examples the status of examples. We used Tall and Vinner’s theoretical framework to analyze the students’ errors that were rooted in mathematical and in real-life contexts.