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Differential EquationsMediumExistence, Uniqueness & Bifurcations

Existence, Uniqueness & Bifurcations · Medium problem

The family y′=y2−ry+4y' = y^2 - ry + 4 has a saddle-node bifurcation at r=4r = 4. For r=5r = 5 it has two equilibria. Which of them is unstable?