To simplify the expression \((2^{-3} \cdot 9^{3})^{-4} / (2^{9} \cdot 9^{-10})\) and find an equivalent expression with only positive exponents, we will use the properties of exponents step by step.
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Apply the Power of a Product Rule: \[ (a \cdot b)^{-n} = a^{-n} \cdot b^{-n} \] Thus, we can distribute the \(-4\) across the terms inside the parentheses: \[ (2^{-3})^{-4} \cdot (9^{3})^{-4} = 2^{12} \cdot 9^{-12} \]
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Rewrite the denominator: The expression now becomes: \[ \frac{2^{12} \cdot 9^{-12}}{2^{9} \cdot 9^{-10}} \]
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Apply the Quotient Rule: Using the property \(\frac{a^m}{a^n} = a^{m-n}\), we can simplify each base:
- For the base \(2\): \[ \frac{2^{12}}{2^{9}} = 2^{12-9} = 2^{3} \]
- For the base \(9\): \[ \frac{9^{-12}}{9^{-10}} = 9^{-12 - (-10)} = 9^{-12 + 10} = 9^{-2} \]
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Combine the results: Thus, the overall expression simplifies to: \[ 2^3 \cdot 9^{-2} \]
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Convert to positive exponents: We can write \(9^{-2}\) as \(\frac{1}{9^2}\): \[ 2^3 \cdot 9^{-2} = \frac{2^3}{9^2} \]
Therefore, the simplified version of the expression with only positive exponents is: \[ \frac{2^3}{9^2} \]
Thus, the equivalent expression to \((2^{-3} \cdot 9^{3})^{-4} / (2^{9} \cdot 9^{-10})\), with only positive exponents, is: \[ \text{Start Fraction 2 cubed over 9 squared end fraction} \]
The correct answer is: \[ \frac{2^3}{9^2} \]