Алина Посадскова (a^(1/3)+b^(1/3))^2-(a^(1/3)-b^(1/3))^2=a^(2/3)+2a^(1/3)*b^(1/3)+b^(1/3)-(a^(2/3)-2a^(1/3)*b^(1/3)+b^(1/3))=a^(2/3)+2a^(1/3)*b^(1/3)+b^(1/3)-a^(2/3)+2a^(1/3)*b^(1/3)-b^(1/3)=4a^(1/3)*b^(1/3)