Some fourth-order nonlinear solvers with closed formulae for multiple roots
In this paper, we present six new fourth-order methods with closed formulae for finding multiple roots of nonlinear equations. The first four of them require one-function and three-derivative evaluation per iteration. The last two require one-function and two-derivative evaluation per iteration. Several numerical examples are given to show the performance of the presented methods compared with some known methods.
multiple roots nonlinear equations newtons method iterative methods root finding