Skip to content
Free public beta until December 4, 2026: every course is open, no card needed. After that, the first chapter of each course stays free and full access is a one-time $39 ($19 for up to 100 founding members chosen for helpful feedback). Your progress is kept. How the beta works

discriminant

b^2-4ac — tells you how many real roots a quadratic has, before solving.

For ax^2+bx+c=0, the discriminant D = b^2-4ac predicts the nature of the roots: D>0 two real roots, D=0 one real root, D<0 no real roots.

Read the full section →
Graph settings

Calculator