3-корень5                   +   3+корень5

дробь                               дробь

3+корень5                        3-корнеь5

(((3-sqrt(5))/((3+sqrt(5))  +((3+sqrt(5))/((3-sqrt(5)) =

=(((3-sqrt(5))*(3-sqrt(5)) +(3+sqrt(5))*(3+sqrt(5)))/(s+sqrt(5))*(3-sqrt(5))=

=(9-6sqrt(5)+5 +9+6sqrt(5)+5)/(9-5)=

=28/4=7