I don't mean to ask without show of any working, but I would like to have some hints, I've tried dividing both sides by (1+h), however, it lead me nowhere.
Any hints as to how I should approach this question?
Hint: by Bernoulli's inequality:
$$ 1+nh \le (1+h)^n \tag{1} $$
Then, since $0 \le h \le 1\,$:
$$ (1+h)^n(1-h)^n = (1-h^2)^n \le 1 \tag{2} $$
Now multiply $(1)$ and $(2)$ together.