T1W8 - 3E4 (Nature of Roots of Quadratic Eqn)

Spent quite some time on helping pupils understand the relationship between the discriminant of a quadratic equation and the nature of its roots by doing the IT worksheet in the A Math Workbook. As the CD provided by the workbook could not work well. I changed to the use of graphmatica and the calculator. They work as well too. After completing the worksheet, pupils were the ones who concluded how discriminant affects the roots of the eqn.

At the same time, they were also able to observe that the sign of the coefficient of x^2 affects the shape of the graph. They were the ones who came up with the conclusion that if the coeff of x^2 is positive, then the graph is a U-shaped curve while negative coefff of x^2 is negative the curve is N-shaped.

Through their own discovery, they are able to remember concepts better. Though it is time consuming to conduct such lesson, it is a worthwhile investment of time. The subsequent lessons (which require pupils to use their newly acquired knowledge to solve related problems) were able to be carried in faster manner.