Đáp án + Giải thích các bước giải:
`1) 2x^2(3x - 5)`
`= 6x^3 - 10x^2`
`2) (x - 3)(6 - 6x^2)`
`= 6x - 6x^3 - 18 + 18x^2`
`3) 2x^2(3x - 5) + (x - 3)(6 - 6x^2)`
`= 6x^3 - 10x^2 - 6x^3 + 18x^2 + 6x - 18`
`= 8x^2 + 6x - 18`
`4) (3x + 5)^2`
`= (3x)^2 + 2.3x.5 + 5^2`
`= 9x^2 + 30x + 25`
`5) (2x - 3)^2`
`= (2x)^2 - 2.2x.3 + 3^2`
`= 4x^2 - 12x + 9`
`6) (3x + 5)^2 - (2x - 3)^2`
`= 9x^2 + 30x + 25 - 4x^2 + 12x - 9`
`= 5x^2 + 42x + 16`
`7) (x - 3)^3`
`= x^3 - 3.x^2 . 3 + 3.x.3^2 - 3^3`
`= x^3 - 3x^2 + 27x - 27`
`8) ( x -3)(x + 3)`
`= x^2 - 3^2 = x^2 -9`
`9) (x + 2)^3`
`= x^3 + 3.x^2 . 2 + 3.x.2^2 + 2^3`
`= x^3 + 6x^2 + 12x + 8`
`10) (x - 3)^3 + (x -3)(x +3) + (x + 2)^3`
`= x^3 - 3x^2 + 27x - 27 + x^2 -9 + x^3 + 6x^2 + 12x + 8`
`= 2x^3 + 4x^2 + 39x - 28`
