# Positive Solutions for Four-Point Boundary Value Problem Involving the $$p(t)$$ p ( t ) -Laplacian

Research paper by Dehong Ji

Indexed on: 13 Aug '16Published on: 01 Apr '16Published in: Qualitative Theory of Dynamical Systems

#### Abstract

Abstract In this paper, by means of the computation of fixed point index, we obtain the existence of positive solutions for four-point boundary value problem involving the $$p(t)$$ -Laplacian \begin{aligned}&(\phi (t,u'(t)))'+ f(t,u(t))=0,\quad t\in (0,1), \\&u'(0)=\alpha u'(\xi ),\quad u(1)=\beta u(\eta ), \end{aligned} where $$\phi (t,x)= x ^{p(t)-2} \ x,\ p\in C([0,1],(1,+\infty )),\ \alpha ,\beta ,\xi ,\eta \in (0,1),\ \xi >\eta ,\ p(0)=p(\xi ),\ f\in C([0,1]\times [0,+\infty ),[0,+\infty ))$$ .AbstractIn this paper, by means of the computation of fixed point index, we obtain the existence of positive solutions for four-point boundary value problem involving the $$p(t)$$ -Laplacian \begin{aligned}&(\phi (t,u'(t)))'+ f(t,u(t))=0,\quad t\in (0,1), \\&u'(0)=\alpha u'(\xi ),\quad u(1)=\beta u(\eta ), \end{aligned} where $$\phi (t,x)= x ^{p(t)-2} \ x,\ p\in C([0,1],(1,+\infty )),\ \alpha ,\beta ,\xi ,\eta \in (0,1),\ \xi >\eta ,\ p(0)=p(\xi ),\ f\in C([0,1]\times [0,+\infty ),[0,+\infty ))$$ . $$p(t)$$ $$p(t)$$ \begin{aligned}&(\phi (t,u'(t)))'+ f(t,u(t))=0,\quad t\in (0,1), \\&u'(0)=\alpha u'(\xi ),\quad u(1)=\beta u(\eta ), \end{aligned} \begin{aligned}&(\phi (t,u'(t)))'+ f(t,u(t))=0,\quad t\in (0,1), \\&u'(0)=\alpha u'(\xi ),\quad u(1)=\beta u(\eta ), \end{aligned} $$\phi (t,x)= x ^{p(t)-2} \ x,\ p\in C([0,1],(1,+\infty )),\ \alpha ,\beta ,\xi ,\eta \in (0,1),\ \xi >\eta ,\ p(0)=p(\xi ),\ f\in C([0,1]\times [0,+\infty ),[0,+\infty ))$$ $$\phi (t,x)= x ^{p(t)-2} \ x,\ p\in C([0,1],(1,+\infty )),\ \alpha ,\beta ,\xi ,\eta \in (0,1),\ \xi >\eta ,\ p(0)=p(\xi ),\ f\in C([0,1]\times [0,+\infty ),[0,+\infty ))$$