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Your goal is to limit the lines to duplicate the picture, right?
It may be possible doing so with a couple of range variables (I guess you would need four different ranges to accomplish the task), but I find it more comfortable to define new functions using the if-function to "plot" NaNs where you don't want to see the line.
I added Eq1 which was missing in your plot.

EDIT: Just for fun I added a way to achieve the same plot using four ranges.
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