Time Invariant Systems
A system is time invariant if for any function x(t), a time shift of the function x(t-t0), is commutative with the other effects of the system. x(t) -> |Sys| -> |time delay by t0| -> a(t) x(t) -> |time delay by t0| -> |Sys| -> a(t) If this resulting function a(t) is the same for both cascades then the system is time invariant.
Time Variant:
A system is time variant if the results of the cascaded systems are not the same.
