giải hộ bài toán skibidi

`@``text{Bơ}`

`(x + 1)^3 + (2 - x)^3 - 9(x - 3)(x + 3) = 0`

`=> x^3 + 3x^2 + 3x + 1 + 8 - 12x + 6x^2 - x^3 - 9(x^2 - 9) = 0`

`=> x^3 + 3x^2 + 3x + 1 + 8 - 12x + 6x^2 - x^3 - 9x^2 + 81 = 0`

`=> (x^3 - x^3) + (3x^2 + 6x^2 - 9x^2) + (3x - 12x) + (1 + 8 + 81) = 0`

`=> -9x + 90 = 0`

`=> -9x = 0 - 90`

`=> -9x = -90`

`=> x = -90 : (-9)`

`=> x = 10`

Vậy `x = 10`