existam vizinhan¸ca U da origem em E e constante ρ ∈ R tais que Φ(u) ≥ ρ para todo u ∈ ∂U, Φ(0) < ρ e Φ(v) < ρ para algum v 6∈ U.
Definimos
c ≡ inf
P ∈Pmaxw∈P Φ(w) ≥ ρ,
em que P denota a classe de caminhos cont´ınuos em E unindo a origem a v 6∈ U. Ent˜ao existe sequˆencia (un) ⊂ E tal que
Φ(un) → c e Φ′(un) → 0 em E∗.
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