Đáp án+Giải thích các bước giải:
`a)x^2-4x^2y^2+y^2+2xy`
`=x^2+2xy+y^2-4x^2y^2`
`=(x+y)^2-(2xy)^2`
`=(x+y-2xy)(x+y+2xy)`
`b)x^6-x^4+2x^3+2x^2`
`=x^4(x^2-1)+2x^2(x+1)`
`=x^4(x-1)(x+1)+2x^2(x+1)`
`=x^2(x+1)[x^2(x-1)+2]`
`=x^2(x+1)(x^3-x^2+2)`
`=x^2(x+1)(x^3+x^2-2x^2+2)`
`=x^2(x+1)[x^2(x+1)-2(x^2-1)]`
`=x^2(x+1)[x^2(x+1)-2(x-1)(x+1)]`
`=x^2(x+1)(x+1)(x^2-2x+2)`
`=x^2(x+1)^2(x^2-2x+2)`
`c)x^3-3x^2+3x-1-y^3`
`=(x-1)^3-y^3`
`=(x-1-y)[(x-1)^2+y(x-1)+y^2]`
`=(x-1-y)(x^2-2x+1+xy-y+y^2)`