Can Greatest integer function and limit be Interchanged

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Consider the Limit

$$ L_1 = \lim_{x \to 0}\left\lfloor\frac{\sin x}{x}\right\rfloor . $$

We have $$ L_1 = \lim_{x \to 0} \left\lfloor \frac{x-\frac{x^3}{6} + \dots}{x} \right\rfloor = \lim_{x \to 0}\left\lfloor{1-\frac{x^2}{6}+\cdots}\right\rfloor . $$ Now my Doubt is what value we will take for $1-\frac{x^2}{6}$ because as per my knowledge limit cannot be taken inside the Greatest integer function.

But where as the Limit

$$L_2 = \left\lfloor\lim_{x \to 0}\frac{\sin x}{x}\right\rfloor=0$$

So are the two limits essentially same, if same does not it mean limit and Greatest integer function are interchanged?

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You have $[1]=1$. Hence $L_2=1$ as $\lim\limits_{x \to 0} \frac{\sin x}{x}=1$.

However $L_1 =0$ as for $x\neq 0$ you have

$$0 < \frac{\sin x}{x} <1.$$

$L_1 \neq L_2$ here and you can’t exchange $\lim$ and $[\cdot ]$ in that case.