х^5-x^4-x-1=0
(x^5-x^4) - (x-1)=0
x^4(x-1) - (x-1)=0
(x^4-1)(x-1)=0
(x^2+1)(x^2-1)(x-1)=0
x^2+1=0
x^2=-1
х^5-x^4-x-1=0
(x^5-x^4) - (x-1)=0
x^4(x-1) - (x-1)=0
(x^4-1)(x-1)=0
(x^2+1)(x^2-1)(x-1)=0
x^2+1=0
x^2=-1