Объяснение:
1)
(12x²-30xy) / (30x²-12xy)= 6x(2x-5y) / (6x(5x-2y) = (2x-5y)/(5x-2y)
2)
(36a²+24ab) / (24a²+36ab) = 12a(3a+2b) / 12a(2a+3b) = (3a+2b)/(2a+3b)
3)
(m³-3m²n)/(3m²n-3m³)=m²(m-3n)/3m²(mn-m)= (m-3n)/3(mn-1)
4)
(a³-2a²b)/(2a³b²-a^4b)=a²(a-2b)/a³b(2b-a)= - a²(2b-a)/a³b(2b-a)=-1/ab
