Failures and Inabilities of High School Students about Quadratic Equations and Functions

In this research study, it was aimed to examine failures and inabilities of eleventh grade students about quadratic equations and functions. For this purpose, these students were asked ten open-ended questions. The analysis of the answers given by the students to these questions indicated that a significant part of these students had failures and inabilities about quadratic equations and functions. The students were often unable to decide what to do in relation to the mathematical operations and made some arithmetical mistakes