`@` `\color[#0c1821][d]``\color[#1b384c][t]``\color[#1f4057][t]`

Đáp án:

a) `x^2-2x+2y-y^2`

`=(x^2-y^2)-(2x-2y)`

`=(x-y)(x+y)-2(x-y)`

`=(x-y)(x+y-2)`

b) `3x^3+xy-12xy^2-2y^2`

`=(3x^3-12xy^2)+(xy-2y^2)`

`=3x(x^2-4y^2)+y(x-2y)`

`=3x(x-2y)(x+2y)+y(x-2y)`

`=(x-2y)[3x(x+2y)+y]`

`=(x-2y)(3x^2+6xy+y)`

c) `x^3+x^2+xy-y^3+y^2`

`=(x^3-y^3)+(x^2+xy+y^2)`

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

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

d) `16x^4-8x^2-y^2+1`

`=(16x^4-8x^2+1)-y^2`

`=(4x^2-1)^2-y^2`

`=(4x^2-y-1)(4x^2+y-1)`