Question

$(frac{a+b}{a})-(frac{a+b}{b}):frac{a+b}{a^{2}b^{2}}$

Answer 1

$frac{a+b}{a}-frac{a+b}{b}:frac{a+b}{a^{2}b^{2}}= frac{a+b}{a}-frac{a^2b^2(a+b)}{b(a+b)}= frac{a+b}{a}-frac{a^3b}{a}= frac{a+b-a^3b}{a}$