I want to set the determinant of the coefficient matrix equal to zero and then solving for the roots. But I could not achieve it via Maple. Can you help me please? 

You can reach two examples in the following file.  Yeni_Microsoft_Word_Belgesi_(2).docx

Besides. how can i compute the following transcental equations via maple 

sinh(beta*L)*sin(beta*L)=0

cosh(beta*L)*cos(beta*L)-1=0

cosh(beta*L)*cos(beta*L)+1=0

regards

mehmet