Question

Let ƒ : R → R satisfy the equation ƒ(x + y) = ƒ(x).ƒ(y) for all x, y ∈ R and f(x) ≠ 0 for any x ∈ R. If the function ƒ is differentiable at x = 0 and ƒ'(0) = 3, then  \(\lim\limits_{h\to0}\frac 1h\)(ƒ(h) -1) is equal to ........

Answer 1

Answer is 3

= 1 x  3 = 3