w(x)=25x^3-x^5
w(x)=-3x^4+6x^3-3x^2
źródło:
w(x)=25x^3-x^5=x^3(25-x^2)=x^3(5-x)(5+x)
w(x)=-3x^4+6x^3-3x^2=-3x^2(x^2-2x+1)=-3x^2(x-1)^2