Question

Помогите пожалуйста

Answer 1

#1
(ac-a²)/c²:(c-a)/c=a(c-a)/c²*c/(c-a)=1/c
#2
(x+y)/y:(x²+2xy+y²)/xy²=(x+y)/y*xy²/(x+y)²=
xy/(x+y)
#3
(x²+2xy+y²)/(x²-y²):(x+y)/1=
(x+y)²/(x-y)(x+y)*1/(x+y)=(x+y)/(x-y)(x+y)=1/(x-y)