Question

$5a {}^{ - 6} \times ( - 3a {}^{ - 2} \times b {}^{3} ) {}^{ - 2} =$
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Answer 1

$5a^{-6}\cdot(-3a^{-2}b^3)^{-2}=5a^{-6}\cdot\dfrac{1}{(-3a^{-2}b^3)^2}=$

$=\dfrac{5a^{-6}}{(-3)^2\cdot(a^{-2})^2\cdot(b^3)^2} =\dfrac{5a^{-6}}{9\cdot a^{-2\cdot2}\cdot b^{3\cdot2}} =$

$=\dfrac{5a^{-6}}{9\cdot a^{-4}\cdot b^6} =\dfrac{5}{9\cdot a^{6-4}\cdot b^6} =\dfrac{5}{9a^2b^6}$