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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">kaz29</journal-id><journal-title-group><journal-title xml:lang="ru">Вестник Казахстанско-Британского технического университета</journal-title><trans-title-group xml:lang="en"><trans-title>Herald of the Kazakh-British Technical University</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1998-6688</issn><issn pub-type="epub">2959-8109</issn><publisher><publisher-name>Казахстанско-Британский Технический Университет</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.55452/1998-6688-2025-22-2-177-187</article-id><article-id custom-type="elpub" pub-id-type="custom">kaz29-1998</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>МАТЕМАТИЧЕСКИЕ НАУКИ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>MATHEMATICAL SCIENCES</subject></subj-group></article-categories><title-group><article-title>ОБ ОДНОЙ АППРОКСИМАЦИИ КРАЕВОЙ ЗАДАЧИ ДЛЯ ИНТЕГРО-ДИФФЕРЕНЦИАЛЬНЫХ УРАВНЕНИЙ С ЗАПАЗДЫВАНИЕМ</article-title><trans-title-group xml:lang="en"><trans-title>ON THE APPROXIMATION OF A BOUNDARY VALUE PROBLEM FOR DELAY INTEGRO-DIFFERENTIAL EQUATIONS</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-3820-5373</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Бакирова</surname><given-names>Э. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Bakirova</surname><given-names>E. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p> канд. физ.-матем. наук, ведущий научный сотрудник </p><p> Алматы </p></bio><bio xml:lang="en"><p> Cand. Phys.-Math. Sc., Leading Researcher </p><p> Almaty </p></bio><email xlink:type="simple">bakirova1974@mail.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-0680-4099</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Искакова</surname><given-names>Н. Б.</given-names></name><name name-style="western" xml:lang="en"><surname>Iskakova</surname><given-names>N. B.</given-names></name></name-alternatives><bio xml:lang="ru"><p> канд. физ.-матем. наук, ведущий научный сотрудник </p><p> Алматы </p></bio><bio xml:lang="en"><p> Cand. Phys.-Math. Sc., Leading Researcher </p><p> Almaty </p></bio><email xlink:type="simple">narkesh77@gmail.com</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-1835-2501</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Иманчиев</surname><given-names>А. Е.</given-names></name><name name-style="western" xml:lang="en"><surname>Imanchiev</surname><given-names>A. E.</given-names></name></name-alternatives><bio xml:lang="ru"><p> канд. физ.-матем. наук, ассоциированный профессор </p><p> Алматы </p><p> Актобе </p></bio><bio xml:lang="en"><p> Cand. Phys.-Math. Sc., Associate Professor </p><p> Almaty </p><p> Aktobe </p></bio><email xlink:type="simple">imanchiev_ae@mail.ru</email><xref ref-type="aff" rid="aff-3"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-7786-5262</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Каракенова</surname><given-names>С. Г.</given-names></name><name name-style="western" xml:lang="en"><surname>Каrakenova</surname><given-names>S. G.</given-names></name></name-alternatives><bio xml:lang="ru"><p> PhD, ст. преподаватель </p><p> Алматы </p><p> Атырау </p></bio><bio xml:lang="en"><p>PhD, Senior Lecturer</p><p>Almaty </p><p>Atyrau </p></bio><email xlink:type="simple">sayakhat.karakenova05@gmail.com</email><xref ref-type="aff" rid="aff-4"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru">Институт математики и математического моделирования;&#13;
Казахский национальный женский педагогический университет<country>Казахстан</country></aff><aff xml:lang="en">Institute of Mathematics and Mathematical Modelingж&#13;
Kazakh National Women's Teacher Training University<country>Kazakhstan</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru">Институт математики и математического моделирования<country>Казахстан</country></aff><aff xml:lang="en">Institute of Mathematics and Mathematical Modeling<country>Kazakhstan</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru">Институт математики и математического моделирования;&#13;
Актюбинский региональный университет им. К. Жубанова<country>Казахстан</country></aff><aff xml:lang="en">Institute of Mathematics and Mathematical Modeling;&#13;
K. Zhubanov Aktobe Regional University<country>Kazakhstan</country></aff></aff-alternatives><aff-alternatives id="aff-4"><aff xml:lang="ru">Институт математики и математического моделирования&#13;
Атырауский университет им. Х. Досмухамедова<country>Казахстан</country></aff><aff xml:lang="en">Institute of Mathematics and Mathematical Modelingж&#13;
Kh. Dosmukhamedov Atyrau University<country>Kazakhstan</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2025</year></pub-date><pub-date pub-type="epub"><day>06</day><month>07</month><year>2025</year></pub-date><volume>22</volume><issue>2</issue><fpage>177</fpage><lpage>187</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Бакирова Э.А., Искакова Н.Б., Иманчиев А.Е., Каракенова С.Г., 2025</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="ru">Бакирова Э.А., Искакова Н.Б., Иманчиев А.Е., Каракенова С.Г.</copyright-holder><copyright-holder xml:lang="en">Bakirova E.A., Iskakova N.B., Imanchiev A.E., Каrakenova S.G.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://vestnik.kbtu.edu.kz/jour/article/view/1998">https://vestnik.kbtu.edu.kz/jour/article/view/1998</self-uri><abstract><p>На конечном интервале исследуется линейная двухточечная краевая задача для системы интегро-дифференциальных уравнений с постоянным запаздывающим аргументом. Делением интервала на части интегральный член интегро-дифференциального уравнения с постоянным запаздывающим аргументом заменяется квадратурной формулой. При такой замене линейная двухточечная краевая задача для системы интегро-дифференциальных уравнений с постоянным запаздывающим аргументом аппроксимируется линейной краевой задачей для системы нагруженных дифференциальных уравнений с постоянным запаздывающим аргументом. Вводятся определения корректной разрешимости как для краевой задачи для системы интегро-дифференциальных уравнений с запаздывающим аргументом, так и для построенной краевой задачи для системы нагруженных дифференциальных уравнений с постоянным запаздыванием. Установлены условия корректной разрешимости линейной краевой задачи для системы интегро-дифференциальных уравнений с запаздывающим аргументом и линейной краевой задачи для системы нагруженных дифференциальных уравнений с запаздывающим аргументом. Показана взаимосвязь между корректными разрешимостями линейной двухточечной краевой задачи для системы интегро-дифференциальных уравнений с постоянным запаздывающим аргументом и аппроксимирующей ее линейной двухточечной краевой задачи для системы нагруженных дифференциальных уравнений с постоянным запаздывающим аргументом.</p></abstract><trans-abstract xml:lang="en"><p>A linear two-point boundary value problem for a system of integro-differential equations with a constant delay argument is investigated on a finite interval. By dividing the interval by parts, the integral term of the integrodifferential equation with constant delay argument is replaced by the quadrature formula. With this replacement, the linear two-point boundary value problem for a system of integro-differential equations with a constant delay argument is approximated by the linear boundary value problem for a system of loaded differential equations with a constant delay argument. Definitions of correct solvability of boundary value problem for system of integro-differential equations with delay argument and constructed boundary value problem for system of loaded differential equations with constant delay argument are introduced. Conditions of correct solvability of linear boundary value problem for system of integro-differential equations with delay argument and linear boundary value problem for system of loaded differential equations with delay argument are established. Relationship between correct solvabilities of linear two-point boundary value problem for system of integro-differential equations with constant delay argument and approximating linear two-point boundary value problem for system of loaded differential equations with constant delay argument is shown.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>интегро-дифференциальное уравнение с запаздыванием</kwd><kwd>нагруженное дифференциальное уравнение с запаздыванием</kwd><kwd>краевая задача</kwd><kwd>корректная разрешимость</kwd><kwd>взаимосвязь</kwd><kwd>аппроксимация</kwd></kwd-group><kwd-group xml:lang="en"><kwd>Delay integro-differential equation</kwd><kwd>delay loaded differential equation</kwd><kwd>boundary value problem</kwd><kwd>correct solvability</kwd><kwd>interrelation</kwd><kwd>approximation</kwd></kwd-group><funding-group xml:lang="ru"><funding-statement>Бұл зерттеулерге Қазақстан Республикасы Ғылым және Жоғары Білім министрлігінің Ғылым комитеті қолдау көрсетті (Грант AP23486114).</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Schmitt K. 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