2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/129097The first order nonlinear ODE d phi(t)/d t + sin phi(t)=B+A cos(omega t), (A,B,omega are real constants) is investigated. Its general solution is derived in the case of the choice of parameters ensuring the phase-lock mode. It is represented in terms of Floquet solution of double confluent Heun equation.28 pagesMathematical Physics34M05text