Polynomial Root Finder

Find real roots of a cubic ax³+bx²+cx+d via Cardano's formula plus the discriminant

Cubic ax³ + bx² + cx + d. Leave a=0 for quadratic, a=b=0 for linear.

Cardano: depressed cubic t³+pt+q=0 with discriminant −(4p³+27q²)
Real roots
1.000000 · 2.000000 · 3.000000
Discriminant
4.000000
Cubic curveSampled cubic curve with real roots marked.3 real roots · Δ 4.001.002.003.00