(x^3+8)÷(x^2-2x+4)
(a^3+27b^3)÷(a+3b)

(x³ + 2³)/(x² -2x +4) =(x+2)(x² -2x +4) /(x² -2x +4)  =  x +2.
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(a³ +(3b)³)/(a+3b) =(a+3b)(a² - 3ab +9b²) / (a+3b) = a² - 3ab +9b² .