“…and a (x) ≡ a, b (x) ≡ b > 0, using Ekeland's variational principle and the mountain-pass lemma Mihȃilescu proved that, if a and b small enough then there are two distinct solutions for the problem; in [22] under the assumptions 1 Mihȃilescu and Rȃdulescu showed that there exists λ * such that any λ ∈ (0, λ * ) is an eigenvalue for the problem by using Ekeland's variational principle and the mountain-pass lemma; in [14] for the case p (x) = q (x) > 1, h (x) = 0, where p (x) is continuous on Ω, and a (x) ≡ 1, b (x) = 0, Fan, Zhang, and Zhao obtained that, Λ = Λ p(x) , the set of eigenvalues, is a nonempty infinite set such that sup Λ = +∞. In addition, they present some sufficient conditions for inf Λ = 0 and for inf Λ > 0, respectively; in [4] under the conditions p (x) = 2, q (x) = 2 and 1 < h < N +2 N −2 , where h is constant, and a (x) , b (x) : Ω ⊂ R N → R are smooth functions which may change sign in Ω, Brown and Zhang used the relationship between the Nehari manifold and fibrering maps to show how existence and nonexistence results for positive solutions of the equation are linked to properties of the Nehari manifold; in [2] Afrouzi, Mahdavi, and Naghizadeh dealt with the similar problem for the case p (x) = q (x) = p, h (x) = h, 1 < h < p, a (x) = 1 and b (x) : Ω ⊂ R N → R is a smooth function which may change sign and they discussed the existence and multiplicity of non-negative solutions of the problem from a variational viewpoint by making use of the Nehari manifold. Under the conditions p…”