Good afternoon, to successfully complete my study on beam vibration i wrote a matlab code to produce all my calculations. This is the beginning of the ocde and shows the point were i get stuck:

prod2=5/2*  3200/4507*sin(pi*alp)*sin(pi*bet)/s*sin(pi*x)*pi^4*sin(pi*y)+19200/4507*sin(pi*alp)*sin(pi*bet)/s^5*sin(pi*x)*sin(pi*y)-6400/4507*sin(pi*alp)*sin(pi*bet)/s^3*sin(pi*x)*pi^2*sin(pi*y))*pi*exp(-5*(x^2-2*x*alp+alp^2-y^2+2*y*bet-bet^2)^(1/2))