Đáp án+Giải thích các bước giải:
`x^5-5x^4+6x^3-x^2+5x-6`
`=x^5-x^4-4x^4+4x^3+2x^3-2x^2+x^2-x+6x-6`
`=x^4(x-1)-4x^3(x-1)+2x^2(x-1)+x(x-1)+6(x-1)`
`=(x-1)(x^4-4x^3+2x^2+x+6)`
`=(x-1)(x^4-3x^3-x^3+3x^2-x^2+3x-2x+6)`
`=(x-1)[x^3(x-3)-x^2(x-3)-x(x-3)-2(x-3)]`
`=(x-1)(x-3)(x^3-x^2-x-2)`
`=(x-1)(x-3)(x^3-2x^2+x^2-2x+x-2)`
`=(x-1)(x-3)[x^2(x-2)+x(x-2)+(x-2)]`
`=(x-1)(x-3)(x-2)(x^2+x+1)`