7-sqrt(24)=7-2sqrt(6)=1-2sqrt(6)+6=(1-sqrt(6))^2=(sqrt(6)-1)^2
sqrt(7-sqrt(24))=sqrt((sqrt(6)-1)^2)=|sqrt(6)-1|=sqrt(6)-1
7+sqrt(24)=7+2sqrt(6)=1+2sqrt(6)+6=(1+sqrt(6))^2=(sqrt(6)+1)^2
(7+sqrt(24))^(4/8)=sqrt((sqrt(6)+1)^2)=|sqrt(6)+1|=sqrt(6)+1
О т в е т. sqrt(6)-1-(sqrt(6)+1)=-2