Answer
`(x + 1)^3 - (x + 1) . (x^2 - x + 1) - 3x . (x - 1)`
`= x^3 + 3x^2 + 3x + 1 - x^3 - 1 - 3x^2 + 3x`
`= (x^3 - x^3) + (3x^2 - 3x^2) + (3x + 3x) + (1 - 1)`
`= 6x`
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`(x - 2)^3 - x . (x - 3)^2 + 1`
`= x^3 - 6x^2 + 12x - 8 - x . (x^2 - 6x + 9) + 1`
`= x^3 - 6x^2 + 12x - 8 - x^3 + 6x^2 - 9x + 1`
`= (x^3 - x^3) + (6x^2 - 6x^2) + (12x - 9x) + (1 - 8)`
`= 3x - 7`