\(\left(x-2\right)\left(x^2+2x+4\right)-\left(x-3\right)^3-\left(x-2\right)^3\)
\(=x^3+2x^2+4x-2x^2-4x-8\) \(-\left(x^3-3x^2.3+3x.3^2-27\right)-\)-\(\left(x^3-3.x^2.2+3.x.2^2-8\right)\)
\(=x^3-8\) \(-x^3+9x^2-27x+27-x^3+6x^2-12x+8\)
\(=-x^3+15x^2-39x+27\)
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