1. **State the problem:** Find the limit as $x \to \infty$ of $$\frac{(3^x - 2)^2}{2 \cdot 9^x}$$.
2. **Rewrite the expression:** Note that $9^x = (3^2)^x = 3^{2x}$. So the expression becomes:
$$\frac{(3^x - 2)^2}{2 \cdot 3^{2x}}$$
3. **Expand the numerator:**
$$(3^x - 2)^2 = (3^x)^2 - 2 \cdot 3^x \cdot 2 + 2^2 = 3^{2x} - 4 \cdot 3^x + 4$$
4. **Substitute back:**
$$\frac{3^{2x} - 4 \cdot 3^x + 4}{2 \cdot 3^{2x}}$$
5. **Split the fraction:**
$$\frac{3^{2x}}{2 \cdot 3^{2x}} - \frac{4 \cdot 3^x}{2 \cdot 3^{2x}} + \frac{4}{2 \cdot 3^{2x}}$$
6. **Simplify each term:**
$$\frac{3^{2x}}{2 \cdot 3^{2x}} = \frac{\cancel{3^{2x}}}{2 \cdot \cancel{3^{2x}}} = \frac{1}{2}$$
$$\frac{4 \cdot 3^x}{2 \cdot 3^{2x}} = \frac{4}{2} \cdot \frac{3^x}{3^{2x}} = 2 \cdot 3^{-x} = \frac{2}{3^x}$$
$$\frac{4}{2 \cdot 3^{2x}} = 2 \cdot 3^{-2x} = \frac{2}{3^{2x}}$$
7. **Rewrite the expression:**
$$\frac{1}{2} - \frac{2}{3^x} + \frac{2}{3^{2x}}$$
8. **Evaluate the limit as $x \to \infty$:**
Since $3^x \to \infty$, both $\frac{2}{3^x} \to 0$ and $\frac{2}{3^{2x}} \to 0$.
Therefore,
$$\lim_{x \to \infty} \frac{(3^x - 2)^2}{2 \cdot 9^x} = \frac{1}{2} - 0 + 0 = \frac{1}{2}$$
**Final answer:** $$\boxed{\frac{1}{2}}$$
Limit Infinity Bb8F37
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