On the balanced pantograph equation of mixed type

UDC 517.9 We consider the balanced pantograph equation (BPE) $y^{\prime}(x)+y(x)=\sum_{k=1}^{m}p_{k}y(a_{k}x),$ where $a_{k}, p_{k} >0$ and $\sum_{k=1}^{m}p_{k} =1.$ It is known that if $K=\sum_{k=1}^{m}p_{k}\ln a_{k} \leq 0$ then, under mild technical conditions, the BPE doe...

Повний опис

Збережено в:
Бібліографічні деталі
Дата:2024
Автори: Derfel, G., Brunt, B. van
Формат: Стаття
Мова:Англійська
Опубліковано: Institute of Mathematics, NAS of Ukraine 2024
Онлайн доступ:https://umj.imath.kiev.ua/index.php/umj/article/view/7654
Теги: Додати тег
Немає тегів, Будьте першим, хто поставить тег для цього запису!
Назва журналу:Ukrains’kyi Matematychnyi Zhurnal
Завантажити файл: Pdf

Репозитарії

Ukrains’kyi Matematychnyi Zhurnal
Опис
Резюме:UDC 517.9 We consider the balanced pantograph equation (BPE) $y^{\prime}(x)+y(x)=\sum_{k=1}^{m}p_{k}y(a_{k}x),$ where $a_{k}, p_{k} >0$ and $\sum_{k=1}^{m}p_{k} =1.$ It is known that if $K=\sum_{k=1}^{m}p_{k}\ln a_{k} \leq 0$ then, under mild technical conditions, the BPE does not have bounded solutions that are not constant, whereas for $K>0$ these solutions exist.  In the present paper, we deal with a BPE of mixed type, i.e., $a_{1}<1<a_{m},$ and prove that, in this case, the BPE has a nonconstant solution $y$ and that $y(x)\sim cx^{\sigma}$ as $x\to \infty,$  where $c>0$ and $\sigma$ is the unique positive root of the characteristic equation $P(s)=1-\sum_{k=1}^{m}p_{k}a_{k}^{-s}=0.$  We also show that $y$ is unique (up to a multiplicative constant) among the solutions of the BPE that decay to zero as $x\to \infty.$
DOI:10.3842/umzh.v75i12.7654