1. **State the problem:** Find the limit $$\lim_{x \to 2} \frac{x^2 - 4}{\sqrt[3]{x - 3} + 1}$$.
2. **Recall the formula and rules:** The limit of a function as $x$ approaches a value is the value the function approaches. If direct substitution leads to an indeterminate form like $\frac{0}{0}$, we simplify the expression.
3. **Evaluate the numerator and denominator at $x=2$: **
- Numerator: $2^2 - 4 = 4 - 4 = 0$
- Denominator: $\sqrt[3]{2 - 3} + 1 = \sqrt[3]{-1} + 1 = -1 + 1 = 0$
Since direct substitution gives $\frac{0}{0}$, we simplify.
4. **Factor the numerator:**
$$x^2 - 4 = (x - 2)(x + 2)$$
5. **Rewrite the limit:**
$$\lim_{x \to 2} \frac{(x - 2)(x + 2)}{\sqrt[3]{x - 3} + 1}$$
6. **Use substitution:** Let $t = \sqrt[3]{x - 3}$, so $t^3 = x - 3$ and $x = t^3 + 3$.
When $x \to 2$, then $t = \sqrt[3]{2 - 3} = \sqrt[3]{-1} = -1$.
Rewrite numerator and denominator in terms of $t$:
- Numerator: $(t^3 + 3 - 2)(t^3 + 3 + 2) = (t^3 + 1)(t^3 + 5)$
- Denominator: $t + 1$
7. **Rewrite the limit in $t$: **
$$\lim_{t \to -1} \frac{(t^3 + 1)(t^3 + 5)}{t + 1}$$
8. **Factor $t^3 + 1$ using sum of cubes:**
$$t^3 + 1 = (t + 1)(t^2 - t + 1)$$
9. **Simplify the expression:**
$$\frac{(t + 1)(t^2 - t + 1)(t^3 + 5)}{t + 1} = (t^2 - t + 1)(t^3 + 5)$$
10. **Evaluate the limit by substituting $t = -1$: **
- $t^2 - t + 1 = (-1)^2 - (-1) + 1 = 1 + 1 + 1 = 3$
- $t^3 + 5 = (-1)^3 + 5 = -1 + 5 = 4$
Multiply:
$$3 \times 4 = 12$$
**Final answer:**
$$\lim_{x \to 2} \frac{x^2 - 4}{\sqrt[3]{x - 3} + 1} = 12$$
Limit Cube Root 99824F
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