Объяснение:
x^2 -3x+1+x^4=x^2-2x+1-x+x^4=(x-1)^2 + x(x^3-1)=(x-1)^2 + x*(x-1)*(x^2+x+1)=
(x-1)(x-1+x*(x^2+x+1)) = (x-1)(x-1+x^3+x^2+x)=(x-1)(x^3+x^2+2x-1)
