The Discriminant

Use the sliders to change the values of a, b, and c.

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Moving sliders b and c will trace the path of the vertex. What do you notice about the trace?
What do you notice about the function when the discriminant is positive?
What conditions of the function produces a negative value for the discriminant?
When is the discriminant zero?

S.H. Lapinski, Created with GeoGebra

Please direct questions and comments to HCPS Mathematics Specialist Henrico County Public Schools, 2009