А) (ах^2-ау)-(bх^2-bу)+(су-сх^2)=а (х^2-у)-b(x^2-y)+c (y-x^2)=a (x^2-y)-b (x^2-y)-c (x^2-y)=(a-b-c)(x^2-y)
А)ах^2-ау-bx^2+cy+by-cx^2=a(x^2-y)-b(x^2-y)-c(x^2-y)=(x^2-y)(a-b-c) B)y^2(x-b+1)-a(x-b+1)=(x-b+1)(y^2-a)