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The variation-of-constants formula and the general solution to degenerate neutral differential systems. (Chinese) Zbl 0962.34060
Summary: The authors study degenerate neutral differential systems; they divide them into three groups of systems, define two kinds of corresponding basic solutions, and find the general solutions to them. Then, the authors give a constant variation formula and the general solution to degenerate neutral differential systems, and give a clear-cut expression for the general solution. The results perfectly extend the fundamental theory of ordinary differential equations and delay differential equations.
MSC:
34K40Neutral functional-differential equations
34K17Transformation and reduction of functional-differential equations and systems; normal forms
34A09Implicit equations, differential-algebraic equations
34K06Linear functional-differential equations