In this paper, by using Krasnoselskii's fixed point theorem of cone expansion–compression type and under suitable conditions, we present the existence of single and multiple positive solutions to the nonlinear second-order m-point boundary value problem u ″ ( t ) + λ a ( t ) f ( u ( t ) ) = 0 , 0 < t < 1 , u ( 0 ) = 0 , u ( 1 ) = ∑ i = 1 m - 2 a i u ( ξ i ) , where λ is a positive parameter, a i ⩾ 0 for i = 1 , 2 , … , m - 3 and a m - 2 > 0 , ξ i satisfy 0 < ξ 1 < ξ 2 < ⋯ < ξ m - 2 < 1 and ∑ i = 1 m - 2 a i ξ i < 1 . We derive an explicit interval of λ such that for any λ in this interval, the existence of at least one positive solution to the boundary value problem is guaranteed, and the existence of at least two solutions for λ in an appropriate interval is also discussed.
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