1. **State the problem:** Rewrite the expression $$\frac{(9^{-3} \cdot 2^{-7})^2}{9^5}$$ using only positive exponents and combine powers with the same base.
2. **Recall exponent rules:**
- Power of a product: $$(a \cdot b)^m = a^m \cdot b^m$$
- Power of a power: $$(a^m)^n = a^{m \cdot n}$$
- Division of same bases: $$\frac{a^m}{a^n} = a^{m-n}$$
- Negative exponent: $$a^{-m} = \frac{1}{a^m}$$
3. **Apply power of a product:**
$$ (9^{-3} \cdot 2^{-7})^2 = 9^{-3 \cdot 2} \cdot 2^{-7 \cdot 2} = 9^{-6} \cdot 2^{-14} $$
4. **Rewrite the original expression:**
$$ \frac{9^{-6} \cdot 2^{-14}}{9^5} $$
5. **Divide powers with the same base 9:**
$$ 9^{-6} \div 9^5 = 9^{-6 - 5} = 9^{-11} $$
6. **Rewrite the expression:**
$$ 9^{-11} \cdot 2^{-14} $$
7. **Rewrite with positive exponents:**
$$ 9^{-11} = \frac{1}{9^{11}}, \quad 2^{-14} = \frac{1}{2^{14}} $$
8. **Final expression:**
$$ \frac{1}{9^{11} \cdot 2^{14}} $$
**Answer:** $$\boxed{\frac{1}{9^{11} \cdot 2^{14}}}$$
Exponent Properties 546930
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