1. What is a cubic?
Examples of cubic expressions include:
(x − 2)3 |
(2x − 3)(x + 6)(x + 2) |
x(x + 1)(x − 1) |
2. Why do quadratics only have two or three terms?
Quad means 4, and quadratics have 4 terms which can simplify to two or three terms.
e.g.
Quadratic
|
Expanded
|
Simplified
|
(x + 2)(x + 3)
|
x2 + 2x + 3x + 6
|
x2 + 5x + 6
|
four terms
|
three terms
|
|
(x + 4)(x − 4)
|
x2 − 4x + 4x − 16
|
x2 − 16
|
four terms
|
two terms
|