Consider the Robin eigenvalue problem. If a0 < 0, al < 0
Chapter 4, Problem 4.3.4(choose chapter or problem)
Consider the Robin eigenvalue problem. If a0 < 0, al < 0 and a0 al < a0all, show that there are two negative eigenvalues. This case may be called substantialabsorptionatbothends.(Hint:Showthattherationalcurve y = (a0 +al)/(2 +a0al) has a single maximum and crosses theline y = 1 in two places. Deduce that it crosses the tanh curve in twoplaces.)
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