Quadratics & Vieta · Difficulty 5/10 · ~40 min
Quadratics & Vieta's Formulas
- Convert between quadratic forms
- Use the discriminant to reason about roots
- Apply Vieta's formulas to symmetric expressions
The quadratic is the most-tested object on the AMC — but the contest never asks you to merely solve one. It asks about roots you never compute: their sum, their squares, their reciprocals. Vieta's formulas are how you answer without solving.