m和n是不为零的互为相反数,m+n=0,m/n=-1,n/m=-1
x和y互为倒数 xy=1
c的绝对值是2 ,c^4=2^4=16
(xy-m/n)^5=2^5=32
c^4/n/m=-16
(x/y)^2004=0
(xy-m/n)^5+(c^4/n/m)-(x/y)^2004=32-16-0=16