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Strong and Quasistrong Disconjugacy

Published online by Cambridge University Press:  20 November 2018

David London
Affiliation:
Department of Mathematics Technion, I.I.T., Haifa Israel
Binyamin Schwarz
Affiliation:
Department of Mathematics Technion, I.I.T., Haifa Israel
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Abstract

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A complex linear homogeneous differential equation of the nth order is called strong disconjugate in a domain G if, for every n points z1,…, zn in G and for every set of positive integers, k1…, kl, k1 + … + kl = n, the only solution y(z) of the equation which satisfies

is the trivial one y(z) = 0. The equation y(n)(z) = 0 is strong disconjugate in the whole plane and for every other set of conditions of the form y(mk(zk) = 0, k = 1 , . . . , n, m1m2... mn, there exist, in any given domain, points z1 , . . . , zn and nontrivial polynomials of degree smaller than n, which satisfy these conditions. An analogous results holds also for real disconjugate differential equations.

Keywords

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1982

References

1. Coppel, W. A., "Disconjugacy", Lecture Notes in Mathematics 220, Springer Berlin, 1971.Google Scholar
2. Elias, U., The extremal solutions of the equation Ly + p(x)y = 0, II J. Math. Anal. Appl. 55 (1976), 253-265.Google Scholar
3. Lavie, M., On disconjugacy and interpolation in the complex domain J. Math. Anal. Appl. 32 (1970), 246-263.Google Scholar
4. London, D. and Schwarz, B., Disconjugacy of complex differential systems and equations, Trans. Am. Math. Soc. 135 (1969), 487-505.Google Scholar
5. Marden, M., "Geometry of Polynomials", 2nd ed., Amer. Math. Soc. Providence R.I., 1966.Google Scholar
6. Pólya, G., On the mean-value theorem corresponding to a given linear homogeneous differential equation, Trans. Am. Math. Soc. 24 (1922), 312-324.Google Scholar
7. Schwarz, B., Norm conditions for disconjugacy of complex differential systems, J. Math. Anal. Appl., 28 (1969), 553-568.Google Scholar
8. Wejntrob, L., Distribution of zeros of a solution for a nondisconjugate differential equation, J. Math. Anal. Appl. 55 (1976), 453-465.Google Scholar