1. **Problem:** Determine the type of discontinuity for the piecewise function
$$f(x) = \begin{cases} 2x^3 + x, & x < -2 \\ x^4 - x^2, & x \geq -2 \end{cases}$$ at $x = -2$.
2. **Step 1: Find $f(-2)$**
Since $x = -2$ falls in the second piece ($x \geq -2$),
$$f(-2) = (-2)^4 - (-2)^2 = 16 - 4 = 12$$
3. **Step 2: Find the left-hand limit $\lim_{x \to -2^-} f(x)$**
Use the first piece:
$$\lim_{x \to -2^-} (2x^3 + x) = 2(-2)^3 + (-2) = 2(-8) - 2 = -16 - 2 = -18$$
4. **Step 3: Find the right-hand limit $\lim_{x \to -2^+} f(x)$**
Use the second piece:
$$\lim_{x \to -2^+} (x^4 - x^2) = (-2)^4 - (-2)^2 = 16 - 4 = 12$$
5. **Step 4: Find the overall limit $\lim_{x \to -2} f(x)$**
Since left and right limits differ,
$$\lim_{x \to -2} f(x) \text{ does not exist (DNE)}$$
6. **Step 5: Compare $f(-2)$ and the limit**
$f(-2) = 12$, but $\lim_{x \to -2} f(x)$ DNE.
7. **Conclusion:**
Because the left and right limits are not equal, the function has a **jump discontinuity** at $x = -2$.
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**Summary:**
- $f(-2) = 12$
- $\lim_{x \to -2^-} f(x) = -18$
- $\lim_{x \to -2^+} f(x) = 12$
- $\lim_{x \to -2} f(x)$ does not exist
- Discontinuity type: **Jump Discontinuity**
Jump Discontinuity F73Ea8
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