Question

x属于零负无穷对于任何x大于一都有x对应的函数值f大于零且fx等于fx加fy，求证f1的值

Answer 1

(1)

∵对一切x.y>0满足f(x/y)=fx-fy

∴当x=y时f(x/y）=f(x/x）=f(1)=fx-fx=0

∴f(1)=0

(2)

∵f(x/y)=fx-fy

f(x+3)-f(1/x)