Students' comparison of their trigonometric answers with the answers of a computer algebra system

摘要

This paper reports on an experiment in which pupils had to solve trigonometric equations by hand and using a computer algebra system (CAS). Many equivalent solutions may be possible for a given trigonometric equation. In the experiment, pupils first solved trigonometric equations without using a CAS. In the second phase, they had to solve the same equations again using a CAS, and then check whether their answers were equivalent to the answers given by the CAS. The complete setup of the experiment is described in the paper. The author explains which equations were chosen. The choice of the equations was dependent on the way the CAS represents the solution. The results of the experiment are then described. For each type of equation, the amount of difficulty faced by the pupils in comparing their own answers with the answers of the CAS is assessed.