TY - JOUR T1 - Nontrivial Solutions for Some Semilinear Elliptic Equations with Critical Sobolev Exponents AU - Wang Chuanfang, Xue Ruying JO - Journal of Partial Differential Equations VL - 1 SP - 77 EP - 96 PY - 1991 DA - 1991/04 SN - 4 DO - http://doi.org/ UR - https://global-sci.org/intro/article_detail/jpde/5763.html KW - Semilinear elliptic equation KW - Sobolev exponent KW - Critical value KW - Critical point KW - (P • S) condition AB - Let Ω be a bounded domain in R^4(n ≥ 4) with smooth boundary ∂Ω. We discuss the existence of nontrivial solutions of the Dirichlet problem {- Δu = a(x) |u|^{4/(a-2)}u + λu + g(x, u), \quad x ∈ Ω u = 0, \quad x ∈ ∂Ω where a(x) is a smooth function which is nonnegative on \overline{Ω} and positive somewhere, λ> 0 and λ ∉ σ(-Δ). We weaken the conditions on a(x) that are generally assumed in other papers dealing with this problem.