So I ran into this problem:
$\lim _{x\to \pi }(\frac{\cos\left(\frac{x}{2}\right)}{\pi ^2-x^2})$
We haven't studied L'Hôpital's rule in my class yet, we basically need to transform the expression using trigonometric identities and use known limits like $\lim_{x \to 0} \frac{sinx}{x} = 1$ to calculate in case we get an indefinite form.
I couldn't find anything I could do to calculate this limit :(
Some help?
Thanks.