sinc cψlx 2 + 12 l2x ∂2 ∂ψ 2 sinc cψlx 2 # =− 6sψ lx j1 cψlx 2

The coefficientsA, Bare fixed by the boundary conditions, that lead to the linear systems   j2 cosh jlx 2lD j∗2 cosh j∗lx 2lD j3 sinh jlx 2lD j∗3 sinh j∗lx 2lD   A A∗ =   l2