The aim of the paper is to study the solvability in the classes of regular solutions of boundary value problems for differential equations ϕ (t)ut - ψ (t)Δu + c(x, t)u = f(x, t) (x ∈ Ω ⊂ ℝn, 0 < t < T). A feature of these equations is that the function ϕ(t) in them can arbitrarily change the sign on the segment [0, T], while the function ψ (t) is nonnegative for t ∈ [0, T]. For the problems under consideration, we prove existence and uniqueness theorems.
- Boundary value problems
- Degenerate parabolic equations
- Regular solutions
- Variable direction of evolution
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