The extended tanh method for new solitons solutions for many forms of the fifth-order KdV equations

The extended tanh method is used to derive new solitons solutions for several forms of the fifth-order nonlinear KdV equation. The forms include the Lax, Sawada–Kotera (SK), Sawada–Kotera–Parker–Dye (SKPD), Kaup–Kupershmidt (KK), Kaup–Kupershmidt–Parker–Dye (KKPD), and the Ito equations. The criteria established in [A.M. Wazwaz, Abundant solitons solutions for several forms of the fifth-order KdV equation by using the tanh method, Appl. Math. Comput., in press, doi:10.1016/j.amc.2006.02.047] to build up reliable relations between the parameters of the equation are confirmed by using this new approach. Entirely new bell shaped solitons are determined.