Question

What is the limit of (1-cos(h))^2 / h as h approaches zero?

Answer 1

Do you know the limit
\[\lim_{h\to0}\frac{1-\cos h}{h}~~~?\]
You can rewrite your limit as
\[\lim_{h\to0}\frac{(1-\cos h)^2}{h}=\lim_{h\to0}\frac{1-\cos h}{h}\cdot\lim_{h\to0}~(1-\cos h)\]

Answer 2

If you're not familiar with that first limit, you could evaluate it using the squeeze theorem.

Answer 3

Thanks. I completely forgot about rewriting the function.

Answer 4

You're welcome