Đáp án:

Giải thích các bước giải:

`1)(x+3)^3`

`=x^3 + 3. x^2 .3 + 3.x. 3^2 +3^3`

`=x^3 + 9x^2 +27x + 27`

`2)(1+x)^3`

`=1^3 + 3. 1^1 .x+3.1 .x^2+x^3`

`=1 + 3x+3x^2+x^3`

`3)(2-x)^3`

`=2^3 - 3 .2^2 .x + 3.2 . x^2 -x^3`

`=8 - 12x + 6x^2 - x^3`

`4)(x-3)^3`

`=x^3 - 3 .x^2 .3 + 3.x . 3^2 - 3^3`

`=x^3 - 9x^2 + 27x - 27`

`5)(2x+1)^3`

`=(2x)^3 + 3. (2x)^2 .1 + 3.2x .1^2 +1^3`

`=8x^3 + 12x^2 + 6x+1`

`6)(3x+2)^3`

`=(3x)^3 + 3. (3x)^2 .2 + 3.3x .2^2+2^3`

`=27x^3 + 54x^2 + 36x+ 8`

`7)(2x-3)^3`

`=(2x)^3 - 3 . (2x)^2 . 3 + 3.2x . 3^2 -3^3`

`=8x^3 - 36x^2 + 54x - 27`

`8)(3x-1)^3`

`=(3x)^3 - 3. (3x)^2 .1 + 3.3x .1^2 - 1^3`

`=27x^3 - 27x^2 + 9x-1`

`9)(x+2y)^3`

`=x^3 + 3. x^2 . 2y + 3.x . (2y)^2 + (2y)^3`

`=x^3 + 6x^2y + 12xy^2 + 8y^2`

`10)(2x+y)^3`

`=(2x)^3 + 3 .(2x)^2 .y + 3.2x. y^2 +y^3`

`=8x^3 + 12x^2y + 6xy^2 +y^3`

`11)(3x-y)^3`

`=(3x)^3 - 3. (3x)^2 .y + 3.3x. y^2 -y^3`

`=27x^3 - 27x^2 y + 9xy^2-y^3`

`12)(x-3y)^3`

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

`=x^3 - 9x^2y + 27xy^2 - 27y^3`

`13)(2x+3y)^3`

`=(2x)^3 + 3 . (2x)^2 . 3y +3.2x . (3y)^2 +(3y)^3`

`=8x^3 + 36x^2y + 54xy^2+27y^3`

`14)(3x+2y)^3`

`=(3x)^3 + 3. (3x)^2 . 2y + 3.3x . (2y)^2 + (2y)^3`

`=27x^3 + 54x^2y + 36xy^2 + 8y^3`

`15)(3x-2y)^3`

`=(3x)^3 - 3. (3x)^2 . 2y + 3.3x . (2y)^2 - (2y)^3`

`=27x^3 - 54x^2y + 36xy^2 - 8y^3`

`16)(4x-y)^3`

`=(4x)^3 - 3. (4x)^2 . y + 3.4x. y^2 - y^3`

`=64x^3 - 48x^3 y + 12xy^2-y^3`