Explore the role of the discriminant in describing the roots of quadratic equations.
This activity encourages students to explore graphically the effect of the discriminant upon a quadratic function. They do this by manipulating a quadratic curve while observing the changing value of the discriminant. They are then asked various questions to help them identify the effect.
There is a 13-page TI-Nspire document that can be used either by students working on individual handhelds or by the teacher using TI-Nspire software projected on a screen to explore the topic with the whole class. There is also a 2-page student worksheet that introduces the task and provides technical help in manipulating graphs on the screen.