Electronic Journal of Differential Equations, Vol. 2007(2007), No. 20, pp. 1-10. Title: Positive solutions for a class of nonresonant boundary-value problems Author: Xuemei Zhang (North China Electric Power Univ., Beijing, China) Abstract: This paper concerns the existence and multiplicity of positive solutions to the nonresonant second-order boundary-value problem $$ Lx=\lambda w(t)f(t,x). $$ We are interested in the operator $Lx:=-x''+\rho qx$ when $w$ is in $L^{p}$ for $1\leq p \leq +\infty$. Our arguments are based on fixed point theorems in a cone and Holder's inequality. The nonexistence of positive solutions is also studied. Submitted November 28, 2006. Published January 27, 2007. Math Subject Classifications: 34B15. Key Words: Positive solution; fixed point theorem; existence; complete continuity.