Limit Infinity 2Ae662
1. **Problem Statement:** Find the limit of a function as $x$ approaches infinity for various types of functions.
2. **General Idea:** The limit at infinity describes the behavior of a function as $x$ becomes very large (positively or negatively).
3. **Common Cases and Formulas:**
- For rational functions $\lim_{x \to \infty} \frac{P(x)}{Q(x)}$, where $P$ and $Q$ are polynomials, the limit depends on the degrees of $P$ and $Q$:
- If degree($P$) < degree($Q$), limit is 0.
- If degree($P$) = degree($Q$), limit is ratio of leading coefficients.
- If degree($P$) > degree($Q$), limit is $\pm \infty$ depending on signs.
- For exponential functions $\lim_{x \to \infty} a^x$ with $a>1$, limit is $\infty$.
- For exponential decay $0 1, limit is $\infty$.
7. **Example 4:** $\lim_{x \to \infty} \frac{\log(x)}{x}$
- Logarithm grows slower than any polynomial.
- Limit is 0.
**Summary:** To find limits at infinity, compare growth rates of numerator and denominator or use known limits of exponential and logarithmic functions.
**Final answers:**
- Example 1: $\frac{3}{2}$
- Example 2: 0
- Example 3: $\infty$
- Example 4: 0