### Possible Answer

The derivatives of trig functions are a bit different. Look at the sine function, and the slope of the sine function - read more

Find the limit: $$\lim_{h \to 0} \frac{f(x+h)-f(x)}{h}$$ Given that $f(x) = \cos(2x)$ Tried many ways, but I kept on getting an indeterminate form. - read more

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