Đáp án:
`(x^4-2x^3-2x^2-2x-3):(x+1)`
`= (x ^4 + x^3 + x^2 + x - 3x^3 - 3x^2 - 3x - 3) : ( x+1)`
`= [ x( x^3 + x^2 + x +1 ) - 3( x^3 + x^2 + x +1)] : ( x +1)`
`= ( x -3)( x^3 + x^2 + x +1) : ( x +1)`
`= ( x -3) [ x^2 ( x +1) + (x +1)] : ( x+1)`
`= ( x -3)( x + 1)( x^2 + 1) : ( x+1)`
`= ( x -3)(x^2 + 1)`