Question 128285
x^3-5x^2+8x-4=0

1 is a root  (sum of coefficients is 0)

doing the division by x-1

    1  -5   8   -4
 1      1  -4    4
    1  -4   4    0

then

x^2-4x+4=0 then (x-2)^2=0  then roots are 
1  and 2(multiplicity 2)