A Note on Klein’s Oscillation Theorem for Periodic Boundary Conditions
M. Faierman · Canadian Mathematical Bulletin · 1975
Recently Howe [4] has considered the oscillation theory for the two-parameter eigenvalue problem 1a 1b subjected to the boundary conditions 2a 2b where for i = 1, 2, — ∞< a i i <∞, and q i are real-valued, continuous functions in [ a i , b i ], p i is positive in [ a i , b i z ], and p i ( a i )= p i ( b i ). Furthermore, it is also assumed that ( A 1 B 2 —A 2 B 1 )≠0 for all values of x 1 and x 2 in their respective intervals.