Nullclines
It is difficult to give a general outline for the determination of nullclines. The key is to set each RHS equal to zero and find all curves on which the resulting equation is satisfied.
x-nullclines
y-nullclines
The complete nullcline plot is the union of the plots of the - and -nullclines.
> NULLplot:=display( [ xNULLplot, yNULLplot ], view=[ -1 .. 3, -1 .. 4 ],
> title=`Nullclines for Competing Species` ):
> NULLplot;
Question
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