Answer
$0$
Work Step by Step
Since we have
$$
\lim _{x \rightarrow 0} \frac{\cos 2x-1}{\sin 5x }=\frac{0}{0}
$$
then we can apply L’Hôpital’s Rule as follows
$$
\lim _{x \rightarrow 0} \frac{-2\sin 2x}{5\cos 5x }=\frac{0}{5}=0.
$$
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