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Title: Closed Loops and RREF as Conceptual Resources for Reasoning about Null Spaces
Vector spaces are often taught with an axiomatic focus, but this has been shown to rely on knowledge many students have not yet developed. In this paper, we examine two students’ conceptual resources for reasoning about null spaces drawing on data from a paired teaching experiment. The task sequence is set in the context of a school with one directional hallways. Students’ informal reasoning about paths that leave the room populations unchanged supported more formal reasoning about null spaces. We found that one student used context-based resources (such as ‘loops’ in hallway) to reason about null spaces, while the other student drew largely on previously formalized mathematical resources (e.g. free variables, linear dependence). The use of formal resources sometimes required recontextualization, which may function to constrain student sense-making or afford opportunities for broadening students’ formal prior knowledge.  more » « less
Award ID(s):
1914793
NSF-PAR ID:
10359026
Author(s) / Creator(s):
Editor(s):
S. S. Karunakaran; A. Higgins
Date Published:
Journal Name:
Proceedings of the 24th conference on research in undergraduate mathematics education
Page Range / eLocation ID:
28-35
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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