Answer:
(a^8)/(b^9)
Explanation:
Two rules of exponents come into play.
(a^b)/(a^c) = a^(b-c)
a^-b = 1/a^b
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Applying the first rule, we have ...
(a^3)/(a^-5) × (b^-2)/(b^7) = a^(3 -(-5)) × b^(-2 -7) = a^8 × b^-9
Applying the second rule gives the simplified form ...
= (a^8)/(b^9)