P1.1.4 - Discriminant of a quadratic

The discriminant of a quadratic function.; Know and use b² − 4ac > 0, b² − 4ac = 0 and b² − 4ac < 0.

Use discriminant of a quadratic to connect the rule to the data and decision in the question.

This matters because discriminant of a quadratic determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply discriminant of a quadratic to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: Discriminant of a quadratic is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.