Abstract
The present study examined students' knowledge after learning the first type of quadratic inequality, ax^2+bx+c>0, a>0, D>0 (D=b^2-4ac). The study also looked at the difference between students with more prior knowledge about the functional approach (high students) and students with less prior knowledge about it (low students). The results showed that most students had knowledge about solving the quadratic equation, but more high students were able to draw the graph than low students. This study also shows that 73.9% of all students acquired strategies with which they could get only answers about specific types of quadratic inequalities, and that there was no difference between high and low students regarding the acquisition of these strategies. The instructions regarding quadratic inequality are also discussed.
