Singular quadratic functionals of one dependent variable with nonseparated boundary conditions are investigated. Necessary and sufficient conditions for nonnegativity of these functionals are derived using the concept of {\it coupled point} and {\it singularity condition}. The paper also includes two comparison theorems for coupled points with respect to the various boundary conditions.
@article{118750, author = {Zuzana Do\v sl\'a and Ond\v rej Do\v sl\'y}, title = {Singular quadratic functionals of one dependent variable}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {36}, year = {1995}, pages = {219-237}, zbl = {0838.34036}, mrnumber = {1357523}, language = {en}, url = {http://dml.mathdoc.fr/item/118750} }
Došlá, Zuzana; Došlý, Ondřej. Singular quadratic functionals of one dependent variable. Commentationes Mathematicae Universitatis Carolinae, Tome 36 (1995) pp. 219-237. http://gdmltest.u-ga.fr/item/118750/
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