Can Steady Solutions of ODEs Be Time-Independent with Small Perturbations?

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I have a set of ODE of the following form

<br /> \begin{cases}<br /> \displaystype{\frac{dx(t)}{dt}} = F(x, y, z; \delta e^{i\omega t}, \Delta e^{-i\omega t})\\[4mm]<br /> \displaystype{\frac{dy(t)}{dt}} = G(x, y, z; \delta e^{i\omega t}, \Delta e^{-i\omega t})\\[4mm]<br /> \displaystype{\frac{dz(t)}{dt}} = H(z, y, z; \delta e^{i\omega t}, \Delta e^{-i\omega t})<br /> \end{cases}<br />

where \delta, \Delta, \omega are constants.

If only concern about the steady solution, can I conclue that the solution must be time-independent?

The equations is quite complicate so one must consider the small pertubration (\delta, \Delta are very small number. So when \delta \to 0 and \Delta \to 0, the steady solutions are x^{(0)}, y^{(0)}, z^{(0)}. Take x as example, the first order corrections of the steady solution is of the form

x = x^{(0)} + y^{(1)} \delta e^{i\omega t} + z^{(1)} \Delta e^{-i\omega t}

I wonder why the above steady solution is time dependent? In this sense, can I conclude that y^{(1)}, z^{(1)} are time independent?
 
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A "steady state solution" is by definition a solution constant in time. Yes, it is independent of time.

Again, the definition of "steady state solution" is that it is time independent!
 
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