Question

Найдите значение выражения.

Answer 1

1
(a-b)/b-(a+b)/a=(a²-ab-ab-b²)=(a²-2ab-b²)/ab
2
1/a²+1/b²=(b²+a²)/a²b²
3
(a²-2ab-b²)/ab*a²b²/(a²+b²)=(a²-2ab-b²)ab/(a²+b²)

(5+4√5+4-2-5+4√5-4)(5-1)/(5+4√5+4+5-4√5+4)=8√5*1/18=4√5/9