【单选题】Dave was newly hired by our company,and he is a good choice for the position since he gained rich experience when he was working for another company .
【简答题】已知f(x)是定义在实数集R上的不恒为0的函数,对任意实数x,y有f(x)f(y)=f(x+y),当x>0时,有0<f(x)<1. (Ⅰ)求f(0)的值,并证明f(x)恒正; (Ⅱ)判断f(x)在实数集R上单调性; (Ⅲ)设S n 为数列{a n }的前n项和,a 1 = 1 3 ,a n =f(n)(n为).令b n =f(S n ),问数列{b n }中是否存在最大项?若存在,求出最大项...