Matlab's error message has told you what one difficulty is. Your input function is returning 'sym' values because you declared s, gamma1, and gamma2 as of type 'sym', and 'integral' expects a numeric type, 'double' or 'single'. You should eliminate the 'syms' declarations.
Also I notice that there are fractional powers of quantities such as
(-(gamma2*25*i)/(1024*pi*s))^(1/3)
where the 1/3 power can yield any one of three possible results. You need to resolve any such ambiguities, or you may get results other than what you expect.
