1. **State the problem:** Find the limit $$\lim_{x \to +\infty} \sqrt[3]{x^2 + x + 1}$$.
2. **Recall the cube root limit rule:** For large $x$, the term with the highest power dominates inside the root. Here, $x^2$ dominates $x$ and $1$.
3. **Rewrite the expression inside the cube root:**
$$\sqrt[3]{x^2 + x + 1} = \sqrt[3]{x^2 \left(1 + \frac{1}{x} + \frac{1}{x^2}\right)}$$
4. **Use the property of roots:**
$$= \sqrt[3]{x^2} \cdot \sqrt[3]{1 + \frac{1}{x} + \frac{1}{x^2}}$$
5. **Simplify the cube root of $x^2$:**
$$\sqrt[3]{x^2} = x^{\frac{2}{3}}$$
6. **Evaluate the limit of the second factor as $x \to +\infty$:**
Since $\frac{1}{x} \to 0$ and $\frac{1}{x^2} \to 0$,
$$\lim_{x \to +\infty} \sqrt[3]{1 + \frac{1}{x} + \frac{1}{x^2}} = \sqrt[3]{1} = 1$$
7. **Combine the results:**
$$\lim_{x \to +\infty} \sqrt[3]{x^2 + x + 1} = \lim_{x \to +\infty} x^{\frac{2}{3}} \cdot 1 = +\infty$$
**Final answer:**
$$\boxed{+\infty}$$
Cube Root Limit 506Bdf
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