Quartic equation
In algebra, a quartic equation is a polynomial of the fourth degree. It is written in the form [math]\displaystyle{ ax^4+bx^3+cx^2+dx+e }[/math].
Quartic Equation Media
Graph of a polynomial function of degree 4, with its 4 roots and 3 critical points.
The quartic formula fully written out in terms of the coefficients of the quartic, for the monic case. Because of its unwieldy nature, it is generally given in terms of auxiliary variables first computed from the coefficients.