... Chair Professor, Mathematics and Statistics Department, King Fahd University of Petroleum andMinerals, Dhahran 31261, Saudi Arabia4Department of Mathematics, National University of Ireland, Galway, ... ProblemsVolume 2009, Article ID 103867, 34 pagesdoi:10.1155/2009/103867 Research Article An Approximation Approach to EigenvalueIntervals for Singular Boundary Value Problemswith Sign Changing and Superlinear ... defined in 2.47.We will prove αn,1is a lower solution of 2.58 and unis an upper solution of 2.58.Now 2.46 and the positivity of ht, s implies that−αn,1tg1t,1n...