I was assigned a problem in my calculus 2 course that I can't seem to solve. We're going over indeterminate forms solved by L'Hopital's Rule.
$$
\lim_{x\to \pi^-}
\left( \frac{\csc(x)+x}{\tan(\frac{x}{2})} \right)
$$
This is in the indeterminate form $ \left[\frac{\infty}{\infty}\right]$, which is given, except I'm not sure why, as $\csc(\pi)$ is undefined. Is this because trig functions occur infinitely (within their range), e.g. $\sin(x) = 1$, occurs for infinite $x$'s?
After applying L'Hopital's Rule, I get:
$$
\lim_{x\to \pi^-}
\left( \frac{-\csc(x)\cot(x) + 1}{\frac{1}{2}\sec^2(\frac{x}{2})} \right)
$$
However, I don't understand how I'm supposed to solve from here. No matter how many times we derive, $\csc(x)$ won't go away and I'm not aware of any trigonometric identities that can simplify the undefined division away. Am I missing something obvious?
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