Practice question · Match the pairs
Match each phase-diagram concept to its description.
- Nullcline
- Stable manifold
- Phase portrait
- Saddle path
- The unique trajectory rational agents choose
- All trajectories in the state-space plane
- Trajectories converging to a saddle equilibrium
- Curve where one variable is not changing
Hints
- Separate the curves where one derivative vanishes from the whole picture.
- One term names the single trajectory that reaches a saddle.
Show the answer
- Nullcline → Curve where one variable is not changing
- Stable manifold → Trajectories converging to a saddle equilibrium
- Phase portrait → All trajectories in the state-space plane
- Saddle path → The unique trajectory rational agents choose
Why
Nullclines, manifolds, portraits, and saddle paths, the geometric language of dynamic systems.
Practise Systems of Differential Equations
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