Example
x3 − 8 =
Re-write as something cubed minus something cubed.
Example
x3 − 8 =
(x)3 − (2)3
=
Use the form: a3 − b3 = (a − b)(a2 + ab + b2).
Example
x3 − 8 =
(x)3 − (2)3
Simplify the expression.
=
(x − 2)(x2 + 2x + 22)
Example
x3 − 8 =
(x)3 − (2)3
Simplify the expression.
=
(x − 2)(x2 + 2x + 22)
=
(x − 2)(x2 + 2x + 4).
Example
27x3 + 8 =
Re-write as something cubed minus something cubed.
Example
27x3 + 8 =
33x3 + 23 =
Re-write as something cubed minus something cubed.
Example
27x3 + 8 =
33x3 + 23 =
(3x)3 + (2)3
=
Use the form: a3 + b3 = (a + b)(a2 − ab + b2).
Example
27x3 + 8 =
33x3 + 23 =
(3x)3 + (2)3
Simplify the expression.
=
(3x + 2)([3x]2 − [3x]2 + 22)
Example
27x3 + 8 =
33x3 + 23 =
(3x)3 + (2)3
Simplify the expression.
=
(3x + 2)([3x]2 − [3x]2 + 22)
=
(3x + 2)(9x2 − 6x + 4).