When we compute a root of equation F(Jf)=0, Mailer's Method uses three initial
approximations XQ, Xi9 and X2 and determines the next approximation Xz by the intersection
of the X-axis with the parabola through (Z0, F(Xfi), (Xl} F(Xl))9 and (X2, F(Xt)). The
procedure is repeated successively to improve the approximate solution of an equation F(X)
=0.