1. **State the problem:** Simplify the expression $$6v^2 \cdot \left(\frac{9u}{v}\right)^7 \cdot \left(\frac{v}{3u}\right)^{-2} \div \left(\frac{9u}{v}\right)^9$$.
2. **Recall the exponent rules:**
- $\left(\frac{a}{b}\right)^m = \frac{a^m}{b^m}$
- $x^{-n} = \frac{1}{x^n}$
- When dividing powers with the same base, subtract exponents: $x^a \div x^b = x^{a-b}$
- When multiplying powers with the same base, add exponents: $x^a \cdot x^b = x^{a+b}$
3. **Rewrite each term with exponents:**
$$6v^2 \cdot \frac{(9u)^7}{v^7} \cdot \left(\frac{v}{3u}\right)^{-2} \div \frac{(9u)^9}{v^9}$$
4. **Simplify the negative exponent:**
$$\left(\frac{v}{3u}\right)^{-2} = \left(\frac{3u}{v}\right)^2 = \frac{(3u)^2}{v^2} = \frac{9u^2}{v^2}$$
5. **Substitute back:**
$$6v^2 \cdot \frac{(9u)^7}{v^7} \cdot \frac{9u^2}{v^2} \div \frac{(9u)^9}{v^9}$$
6. **Rewrite division as multiplication by reciprocal:**
$$6v^2 \cdot \frac{(9u)^7}{v^7} \cdot \frac{9u^2}{v^2} \cdot \frac{v^9}{(9u)^9}$$
7. **Group like terms:**
$$6 \cdot 9 \cdot (9u)^7 \cdot u^2 \cdot v^{2 - 7 - 2 + 9} \cdot \frac{1}{(9u)^9}$$
Calculate the exponent of $v$:
$$2 - 7 - 2 + 9 = 2$$
8. **Simplify powers of 9 and u:**
$$(9u)^7 \cdot u^2 = 9^7 u^7 \cdot u^2 = 9^7 u^{9}$$
Divide by $(9u)^9 = 9^9 u^9$:
$$\frac{9^7 u^9}{9^9 u^9} = 9^{7-9} u^{9-9} = 9^{-2} = \frac{1}{9^2} = \frac{1}{81}$$
9. **Combine constants:**
$$6 \cdot 9 \cdot \frac{1}{81} = \frac{54}{81} = \frac{2}{3}$$
10. **Combine all factors:**
$$\frac{2}{3} \cdot v^2 = \frac{2}{3} v^2$$
**Final answer:** $$\boxed{\frac{2}{3} v^2}$$
Simplify Expression 47A2B6
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