A quadratic function is a function of the form <math>f(x)=ax^2+bx+c</math>, where a is nonzero.
In the case where the domain and codomain are R (the real numbers), the graph of such a function is a parabola.
... saw the Peasants' Revolt in Germany and the formation of the Lutheran Schmalkaldic League, and Charles delegated increasing responsibility for Germany to his broth ...