has solutions in radicals if and only if it has an integer solution or r is one of ±15, ±22440, or ±2759640, in which cases the polynomial is reducible. As solving reducible quintic equations reduces ...
Sedletsky, Yu. V. and Gandzha, I.S. 2022. Hamiltonian form of an Extended Nonlinear Schrödinger Equation for Modelling the Wave field in a System with Quadratic and Cubic Nonlinearities. Mathematical ...