I have a simple question regarding nullclines, as I'm having trouble determining the correct direction errors.
For example, here's a system of equations:
dx/dt = 2-x-y
x-null is y= -x + 2
y-null is y= x^2
x-null is vertical, y-null goes horizontal.
But when I divide the graph in different sections, and pick different plot points which equations do I plug into to find directions?
I know that wasn't clear, but for example:
If I want to know if on the y-null if the direction of a certain section is pointing left or right, would I plug the points I chose in:
A) dy/dt = y-X^2
or C) y=x^2
I'm not sure which equation to plug it in. I've tried to think it out, but I end up always confusing myself. Please point me in the right direction. Thanks.