Definition:Cubic Equation

Definition
Let $f \left({x}\right) = a x^3 + b x^2 + c x + d$ be a polynomial function over a field $K$ of degree $3$.

Then the equation $f \left({x}\right) = 0$ is the general cubic equation (or just cubic) over $K$.

Also see

 * Cardano's Formula: an algebraic technique for finding its roots.