5a^2-35/a-sqrt(7)
5(a^2-7)/a-sqrt(7)
5(a-sqrt(7))*(a+sqrt(7))/a-sqrt(7)
5(a+sqrt(7))
16+6sqrt(7)) =9+6sqrt(7))+7=(3+sqrt(7))^2sqrt(16+6sqrt(7))=sqrt((3+sqrt(7))^2)=3+sqrt(7)
sqrt-корень
5a^2-35/a-sqrt(7)
5(a^2-7)/a-sqrt(7)
5(a-sqrt(7))*(a+sqrt(7))/a-sqrt(7)
5(a+sqrt(7))
16+6sqrt(7)) =9+6sqrt(7))+7=(3+sqrt(7))^2
sqrt(16+6sqrt(7))=sqrt((3+sqrt(7))^2)=3+sqrt(7)
sqrt-корень