A cura di: Alfredo Bochicchio

$[(-ab^2)^2+1/3a^2b^4]:(ab^2)^2-(1/2a^2b)^2:[(3/4ab)^2(-a)^2]$
$[a^2b^4+1/3a^2b^4]:(a^2b^4)-(1/4a^4b^2):[9/16a^4b^2]$
$[4/3a^2b^4]:(a^2b^4)-4/9$
$4/3-4/9$
$8/9$