Which product will result in a sum or difference of cubes?
(x + 7)(x2 – 7x + 14)
(x + 8)(x2 + 8x + 64)
(x – 9)(x2 + 9x + 81)
(x – 10)(x2 – 10x + 100)

Formulas of sum and difference of cubes.

a³ + b³ = (a + b) (a² - ab + b²)
a³ - b³  = (a - b) (a² + ab + b²)

First, we need to compare the sign of operation. Then, we raise both a and b to its 2nd power.

Among the choices, only (x - 9)(x² + 9x + 81) follows the correct format of the signs of operation.

x (x² + 9x + 81) - 9(x² + 9x +81)
x³ + 9x² + 81x - 9x² -81x - 729
x³ + 9x² - 9x² + 81x - 81x - 729
x³ - 729  DIFFERENCE OF CUBES

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