Suppose that f : R → (0, ∞) satisfies f(x + y) = f(x)/(y). Modifying the outline in Exercise 3.3.8, show that if f is continuous at 0, then there is an a ∊ (0, ∞) such that f(x) = ax for all x ∊ R. (You may assume that the function ax is continuous on R.)