1. **State the problem:** Find the limit
$$\lim_{x \to \infty} \frac{\ln(x^2 + 3x + 2) - \ln(x^2 - 4x + 2)}{x^2}$$
2. **Use logarithm properties:** Recall that \(\ln a - \ln b = \ln \frac{a}{b}\). So rewrite the expression as
$$\lim_{x \to \infty} \frac{\ln \left( \frac{x^2 + 3x + 2}{x^2 - 4x + 2} \right)}{x^2}$$
3. **Analyze the fraction inside the logarithm:**
$$\frac{x^2 + 3x + 2}{x^2 - 4x + 2} = \frac{x^2(1 + \frac{3}{x} + \frac{2}{x^2})}{x^2(1 - \frac{4}{x} + \frac{2}{x^2})} = \frac{1 + \frac{3}{x} + \frac{2}{x^2}}{1 - \frac{4}{x} + \frac{2}{x^2}}$$
4. **Take the limit inside the logarithm as \(x \to \infty\):**
$$\lim_{x \to \infty} \frac{1 + \frac{3}{x} + \frac{2}{x^2}}{1 - \frac{4}{x} + \frac{2}{x^2}} = \frac{1 + 0 + 0}{1 - 0 + 0} = 1$$
5. **Use the fact that \(\ln(1) = 0\), so the numerator tends to \(\ln(1) = 0\).**
6. **Since the numerator tends to 0 and the denominator tends to infinity \((x^2 \to \infty)\), the whole fraction tends to 0.**
7. **To be rigorous, use the expansion for logarithm near 1:**
Set
$$y = \frac{1 + \frac{3}{x} + \frac{2}{x^2}}{1 - \frac{4}{x} + \frac{2}{x^2}} = 1 + \frac{7}{x} + O\left(\frac{1}{x^2}\right)$$
Then
$$\ln(y) \approx \frac{7}{x} + O\left(\frac{1}{x^2}\right)$$
8. **Substitute back into the limit:**
$$\lim_{x \to \infty} \frac{\ln(y)}{x^2} \approx \lim_{x \to \infty} \frac{\frac{7}{x} + O(\frac{1}{x^2})}{x^2} = \lim_{x \to \infty} \left( \frac{7}{x^3} + O\left(\frac{1}{x^4}\right) \right) = 0$$
**Final answer:**
$$\boxed{0}$$
Limit Logarithms D8E15E
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