Periodic solutions for a kind of Rayleigh equation with a deviating argument Original Research Article

By employing the coincidence degree theory of Mawhin, we study a kind of Rayleigh equation with a deviating argument as follows: x″(t) + f (x′(t)) + g(x(t − τ(t))) = p(t). Some new results on the existence of periodic solutions are obtained. Our results generalize corresponding work in the past.