Reading data from Graphs: a study on the role of language

The work described in this paper is framed in a larger study focused on written argumentations produced by university students in tasks regarding graphs, conversions between graphs and their analytic properties and relations among different graphs. Using the functional linguistics framework, we analyse difficulties related to an examination task on functions and their derivatives. The use of colloquial and literate registers in mathematics problem solving is the lens through which we analyse and discuss the errors. We draw attention to the difficulties concerning the use of literate registers and how these difficulties influence the errors in the interpretations of texts and figures