How to replace 7th-row(second last) of the matrix H116 (see eq. (14)) with the 1st-row of the matrix H16 (see eq. (15)) and create a new matrix of size same as H116?

matrixop.mw

During evaluating psi0 (see eq, (7)), why we need two values of f (i.e., f,0 and f,3)? I asked one of my seniors and according to him these values are arbitrary. Can anyone explain why we need two values and why f,0 and f,3?

rwo.mw  

I try to simplify the expression by putting exponential function into equation but the maple shows error which I can't fix it.simplification.mw

I am trying to find the solution (\Psi) as f approaches zero. However, after applying the limit the solution becomes zero. See the attached .mw file.limit.mw

How to simplify the product of 4x4 matrices and how can we take out the expression that appears in each entry of the matrix?

MLM-1.mw