(1) g(e)=ae-b/e-2lne=ae-b/e-2
而g(e)=be-a/e-2
所以ae-b/e=be-a/e
所以a=b
(2)g'(x)=a+a/x^2-2/x
当x>0时要使g'(x)>0,需a>0且4-4a^2