| Abstrakt: |
We establish the existence of at least three positive periodic solutions to the second order differential equation with periodic coefficients \[ \hspace*{6pc} -(p(t)x'(t))'+q(t)x(t)=f(t,x(t)),\quad t\in R,\hspace*{6.4pc}(\ast) \] where f is continuous with f(t + T, x) = f(t,x) for (t,x) ∊ R × R and T > 0, p, q are continuous and T-periodic with p > 0 and q ≥ 0. We accomplish this by making growth assumptions on f, which can apply to many more cases than those discussed in recent works. An example to illustrate the main result is given. [ABSTRACT FROM AUTHOR] |
