x'1= -x1
x'2 = -x2 + x21
x'3 = x3 + x22

Using Perko's method, compute the first 3 approximations of the stable and unstable
manifolds at the steady state (0,0,0).

I can get the stable, but don't understand how to do the unstable.
http://www.cds.caltech.edu/~murray/w...Week4Notes.pdf

shows perkos method for stable but not unstable, it says to switch t for -t to do unstable, but i get infinity for x3. I don't think I should be getting that. help please!