Periodic solution for a class of Duffing equations with delay. (Chinese. English summary) Zbl 1117.34308
Summary: Duffing equation
\[
ax''(t)+f(x(t))x'(t)+ bx(t)+g(x(t-\tau(t)))=p(t)
\]
is considered. Using the theory of coincidence degree, sufficient conditions for the existence of at least a \(2\pi\)-periodic solution are obtained.
MSC:
34K13 | Periodic solutions to functional-differential equations |