Sine: explorative model
Objective and steps
Students work in pairs (two student, A and B).
1) Student A introduces a numerical value for the the acute angle () in the dynamic model, and this value remains unchanged until step (5). Then, student A drags the orange point to modify the base-length of the triangle.
2) Student B writes down the values of the triangle from the model and performs calculations in paper with the given information.
3) Students switch positions. Student B decides a new position for the orange point (without changing the angle, since the “input box” is gone for the moment), and student A performs new calculations. Students repeat steps (2) and (3) a number of times.
4) Students must formulate a conjecture and the conjecture must be coherent with the obtained data.
5) Students push the “new angle” button, and they start again from step (1) with a new triangle.
6) After repeating the process with a number of triangles, students reformulate their conjecture, which must be coherent with the obtained new data.