Factoring Flashcards
“Expanding”
Using the Distributive Law to expand certain algebraic expressions.
“Factoring”
Using the Distributive Law to factor certain algebraic expressions as the product of a simpler one by extracting common factors within an expression.
Describe how to factor a quadratic of the form x^2 + bx + c
x^2 + bx + c
(x + r)(x + s) = x^2 + (r + s)x + rs; Choose values for r and s so that r + s = b and rs = c.
Factor: a^2 - b^2
a^2 - b^2 = (a - b)(a + b)
What is the analogous formula for a difference of cubes?
a^3 - b^3 = (a - b)(a^2 + ab + b^2)
What is the analogous formula for a sum of cubes?
a^3 + b^3 = (a + b)(a^2 - ab + b^2)
What is the Factor Theorem?
If P is a polynomial and P(b) = 0, then x - b is a factor of P(x)