Вправа 201 - 300 » 280

280. Виконай ділення. a) (a^2- 2a+1)/(a^2+ 2a+1) : (5a-5)/(〖3a〗^3+ 3) = (〖(a-1)〗^2 •3〖(a〗^3+ 1))/(〖(a+1)〗^2 •5(a-1)) = (3(a-1) 〖(a〗^2- a+1))/(5(a+1)); б) (1- x^2 y^2)/(1+xy) : (xy-1)/(〖xy〗^2+ y) = ((1-xy)•y(xy+1))/(xy-1) = –y(1 + xy); в) (4a2 – 1) : (1+2a)/(1-2a) = ((2a-1)(2a+1)•(1-2a))/(1+2a) = –(2a – 1)2; г) (3-x)/(3+x) : (x2 – 9) = ((3-x))/((x-3)(3+x)(x+3)) = –1/〖(x+3)〗^2 .