1. **State the problem:** We are given the equation $$\frac{-2x - 12}{x (x - 2) (x + 2)} = \frac{A}{x} + \frac{-2}{x - 2} + \frac{-1}{x + 2}$$ and need to find the value of $A$.
2. **Use the formula for partial fraction decomposition:** The expression on the left is decomposed into partial fractions on the right. Each term corresponds to one factor in the denominator.
3. **Multiply both sides by the common denominator** $x (x - 2) (x + 2)$ to clear fractions:
$$-2x - 12 = A (x - 2)(x + 2) + (-2) x (x + 2) + (-1) x (x - 2)$$
4. **Expand each term:**
- $A (x - 2)(x + 2) = A (x^2 - 4)$
- $-2 x (x + 2) = -2 (x^2 + 2x) = -2x^2 - 4x$
- $-1 x (x - 2) = -1 (x^2 - 2x) = -x^2 + 2x$
5. **Combine all terms on the right:**
$$-2x - 12 = A x^2 - 4A - 2x^2 - 4x - x^2 + 2x$$
6. **Group like terms:**
$$-2x - 12 = (A x^2 - 2x^2 - x^2) + (-4x + 2x) - 4A$$
$$-2x - 12 = (A - 3) x^2 - 2x - 4A$$
7. **Match coefficients of powers of $x$ on both sides:**
- Coefficient of $x^2$: Left side has 0, so $A - 3 = 0$ which gives $A = 3$
- Coefficient of $x$: Left side is $-2$, right side is $-2$, consistent.
- Constant term: Left side is $-12$, right side is $-4A = -4(3) = -12$, consistent.
**Final answer:**
$$\boxed{3}$$
Partial Fraction 4382C9
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