Limiti Funzione
1. **Stating the problem:**
We need to find the limits of the function $f(x)$ at various points based on the graph.
2. **Recall limit definitions:**
- The limit $\lim_{x \to a} f(x)$ is the value that $f(x)$ approaches as $x$ gets arbitrarily close to $a$.
- The left-hand limit $\lim_{x \to a^-} f(x)$ is the value $f(x)$ approaches as $x$ approaches $a$ from the left.
- The right-hand limit $\lim_{x \to a^+} f(x)$ is the value $f(x)$ approaches as $x$ approaches $a$ from the right.
- If left and right limits differ, the two-sided limit does not exist.
3. **Analyze each limit from the graph:**
**a.** $\lim_{x \to 0} f(x)$: The graph approaches $y=3$ near $x=0$ with a dashed line, indicating the limit is 3.
**b.** $\lim_{x \to 1^-} f(x)$: Approaching $x=1$ from the left, the graph rises steeply to about $y=6$.
**c.** $\lim_{x \to 1^+} f(x)$: Approaching $x=1$ from the right, the graph slopes downward from the open circle at $y=4$ and continues smoothly, so the right limit is $4$.
**d.** $\lim_{x \to 1} f(x)$: Since left limit ($6$) and right limit ($4$) differ, the two-sided limit does not exist.
**e.** $\lim_{x \to +\infty} f(x)$: The graph declines toward zero as $x$ goes to infinity, so the limit is $0$.
4. **Final answers:**
$$
\begin{aligned}
&\text{a. } \lim_{x \to 0} f(x) = 3 \\
&\text{b. } \lim_{x \to 1^-} f(x) = 6 \\
&\text{c. } \lim_{x \to 1^+} f(x) = 4 \\
&\text{d. } \lim_{x \to 1} f(x) \text{ does not exist} \\
&\text{e. } \lim_{x \to +\infty} f(x) = 0
\end{aligned}
$$