SOLUTION: factor. x^3 + (x + 3)^3

Factor x³ + (x+3)³

Let y = x+3, then the above becomes:

x³ + y³

By the method for factoring the sum of two cubes,
the above becomes:

(x + y)(x² - xy + y²)

Change the parentheses to brackets

[x + y][x² - xy + y²]

Replace the y's by (x+3)

[x + (x+3)][x² - x(x+3) + (x+3)²]

[x + x + 3][x² - x² - 3x + (x+3)(x+3)]

[2x + 3][-3x + (x²+3x+3x+9)]

[2x + 3][-3x + (x²+6x+9)]

[2x + 3][-3x + x² + 6x + 9]

[2x + 3][x² + 3x + 9]

Change the brackets to parentheses:

(2x + 3)(x² + 3x + 9)

Edwin