In this paper we introduce the definition of coupled point with respect to a (scalar) quadratic functional on a noncompact interval. In terms of coupled points we prove necessary (and sufficient) conditions for the nonnegativity of these functionals.
@article{118510, author = {Zuzana Do\v sl\'a and PierLuigi Zezza}, title = {Quadratic functionals with a variable singular end point}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {33}, year = {1992}, pages = {411-425}, zbl = {0779.49026}, mrnumber = {1209284}, language = {en}, url = {http://dml.mathdoc.fr/item/118510} }
Došlá, Zuzana; Zezza, PierLuigi. Quadratic functionals with a variable singular end point. Commentationes Mathematicae Universitatis Carolinae, Tome 33 (1992) pp. 411-425. http://gdmltest.u-ga.fr/item/118510/
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