a³ − b³ = (a − b)(a² + ab + b²). a³ + b³ = (a + b)(a² − ab + b²). Factoring as a set is in factoring quadratics.
SOAP for the signs
Same, Opposite, Always Positive on the second factor. Difference of squares is the two-term cousin, in difference of squares. Perfect-square trinomials are a different leftover, in perfect-square trinomials.
The bottom line
Cubes split into a linear factor and a quadratic. Watch the middle sign.
Start practicing
Start with a free diagnostic, then drill your weak spots with 15-question quizzes and track how you're doing across Reading, English, and Math. Compare plans whenever you're ready to go further.
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