f '(x)=-1/(5+2x)^2·2f ''(x)=(-1)·(-2)/(5+2x)^3·2^2f '''(x)=(-1)·(-2)·(-3)/(5+2x)^4·2^3归纳得出,f(x)的n阶导数是(-1)·(-2)·(-3)·……·(-n)/(5+2x)^(n+1)·2^n=(-1)^n·n!/(5...