câu c và dddddđ aaaaaaaaaa

`c, 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)^2 [x^2 - 2(x - 1)]`

`= x^2 (x + 1)^2 (x^2 - 2x + 2)`

`d, x^3 - 3x^2 + 3x - 1 - y^3`

`= (x - 1)^3 - y^3`

`= (x - 1 - y)[(x - 1)^2 + (x - 1)y + y^2]`

`= (x - y - 1)(x^2 - 2x + 1 + xy - y + y^2)`