Study of Fouchik Sрectrum Using Imрlicit Functional

The eigenvalue problem for the equation -Δu - λ₊u⁺ + λ_-u^- = 0 is examined in the domain Ω ⊂ R^N. By comparing homotopic set types of the lesser values of the built functional it is possible to establish the existence of spectrum points in the wider domain on the plane {(λ₊, λ_-)}.