Evaluating $\lim_{x\rightarrow \infty}\frac{x+\sin{x}}{x+2\sin{x}}$ in two ways gives different answers

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$$\lim_{x\rightarrow \infty}\frac{x+\sin{x}}{x+2\sin{x}}$$ I have obtained different answers while using two different methods.

method1 : splitting the function into two parts $$\lim_{x\rightarrow \infty}\frac{x+2\sin{x}}{x+2\sin{x}} - \lim_{x\rightarrow \infty}\frac {\sin{x}}{x+2\sin{x}} $$ now, clearly the value of limits can be observed as 1-0=1

method2 : using L'Hospital's Rule the given expression can be written as
$$\lim_{x\rightarrow \infty}\frac{1+\cos{x}}{1+2\cos{x}}$$

now,clearly we can see that limit to the above expression does not exist.

WHICH METHOD IS WRONG AND WHY??

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The second one is wrong. L'Hopital's Rule states that, under certain conditions, if the limit $\lim_{x\to\infty}\frac{f'(x)}{g'(x)}$ exists, then $\lim_{x\to\infty}\frac{f(x)}{g(x)}=\lim_{x\to\infty}\frac{f'(x)}{g'(x)}$. It says nothing about what happens when the limit $\lim_{x\to\infty}\frac{f'(x)}{g'(x)}$ does not exist.