1. **Problem statement:** Given the function $$f(x) = 2x - 5 - 4xe^{-0.5x}$$ defined on $$[0,+\infty[$$, determine $$\lim_{x \to +\infty} f(x)$$.
2. **Formula and rules:** To find the limit of $$f(x)$$ as $$x \to +\infty$$, analyze each term separately. Recall that $$\lim_{x \to +\infty} e^{-ax} = 0$$ for any positive constant $$a$$.
3. **Intermediate work:**
$$\lim_{x \to +\infty} f(x) = \lim_{x \to +\infty} \left(2x - 5 - 4xe^{-0.5x}\right) = \lim_{x \to +\infty} (2x - 5) - \lim_{x \to +\infty} 4xe^{-0.5x}$$
4. The first limit is:
$$\lim_{x \to +\infty} (2x - 5) = +\infty$$
5. For the second limit, use the fact that exponential decay dominates polynomial growth:
$$\lim_{x \to +\infty} 4xe^{-0.5x} = 0$$
6. Therefore,
$$\lim_{x \to +\infty} f(x) = +\infty$$
**Final answer:** $$\lim_{x \to +\infty} f(x) = +\infty$$
Limit Infinity 1C7Dae
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