x3 _ x2 _ 4x - 4 = 0
x mũ 2(x+1)- 4(x+1)=0
(x mũ 2 - 4) (x+1)=0
(x+2) (x-2) (x+1) =0
suy ra (x+2)=0
(x-2)=0
(x+1)=0
vậy x=-2
x=2
x= -1
good luck!
Sửa đề : \(x^3-x^2-4x+4=0\)
\(\Leftrightarrow x^2\left(x-1\right)-4\left(x-1\right)=0\)
\(\Leftrightarrow\left(x^2-4\right)\left(x-1\right)=0\)
\(\Leftrightarrow\left(x-2\right)\left(x+2\right)\left(x-1\right)=0\Leftrightarrow x=\pm2;1\)
`x^4-x^3-4x-4=0`
`x^3(x-1)-4(x-1)=0`
`(x^3-4)(x-1)=0`
Suy ra `x^3-4=0` hoặc `x-1=0`
Suy ra `x^3=4` hoặc `x=1`
Suy ra `x=`$sqrt[3]{4}`$ hoặc `x=1`
Vậy...


