1. **State the problem:** We have a piecewise function
$$f(x) = \begin{cases} 4x^2 + ax - 1 & \text{if } 0 \leq x < 2 \\ 3x + a & \text{if } x > 2 \end{cases}$$
We want to find the values of $a$ and $L$ such that
$$\lim_{x \to 2} f(x) = L$$
2. **Recall the limit condition for piecewise functions:** For the limit at $x=2$ to exist, the left-hand limit and right-hand limit must be equal:
$$\lim_{x \to 2^-} f(x) = \lim_{x \to 2^+} f(x) = L$$
3. **Calculate the left-hand limit:**
$$\lim_{x \to 2^-} f(x) = \lim_{x \to 2^-} (4x^2 + ax - 1) = 4(2)^2 + a(2) - 1 = 16 + 2a - 1 = 15 + 2a$$
4. **Calculate the right-hand limit:**
$$\lim_{x \to 2^+} f(x) = \lim_{x \to 2^+} (3x + a) = 3(2) + a = 6 + a$$
5. **Set the limits equal to find $a$:**
$$15 + 2a = 6 + a$$
Subtract $a$ from both sides:
$$15 + \cancel{2a} - \cancel{a} = 6 + \cancel{a} - \cancel{a} \implies 15 + a = 6$$
Subtract 15 from both sides:
$$\cancel{15} + a - \cancel{15} = 6 - 15 \implies a = -9$$
6. **Find $L$ by substituting $a = -9$ into either limit:**
Using right-hand limit:
$$L = 6 + a = 6 + (-9) = -3$$
**Final answers:**
$$a = -9$$
$$L = -3$$
Limit Piecewise 4712E3
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