integral exponents

Question

simplify (a^2b)^-1 (a^-2+b^-2)^-1

Answer 1

(a^2b)^-1 (a^-2+b^-2)^-1

= 1/(a^2b) * 1/(1/a^2 + 1/b^2)

= b/(a^2+b^2), after multiplying the top and the bottom by (a^2 b^2).