1)
а) = (a+b)/a*(a²/c(a+b) =a/c.
б) =(4a³/(5b))² =(16/25)*a^6/b².
в) =b/(a(a+b)) : b/((a-b)(a+b)) =b(a-b)(a+b)/(a(a+b)b=(a - b)/b.
д) =(c-d)(c+d) *c/3(c+d) =c(c-d)/3.
2.
=(1/(a-b) -1/(a+b) )*(a²-b²)/b² =(1/(a-b) -1/(a+b) )*(a- b)(a+b)/b² =
(a+b -(a-b))*1/b² =2b/b² =2/b.
3. =(a-7)²/(3(a+2))*6(a+2)/(a-7)(a+7) =2(a-7)/(a+7) =\a=7,5\ =2(7,5-7)* (7,5+7)=2*0,5*14,5=1*14,5 =14,5
4. = (1/(a-b)*2(a-b)/ab -(a²+b²)/(ab)²)*a²b²/(a² -b²) =
- (a² - 2ab+b²)/(ab)² *a(b)²/(a-b)(a+b) =-(a-b)²/(a-b)(a+b) = -(a-b)/(a+b) =(b-a)/(b+a).