Thursday, November 25, 2010

Identifying Different Situations In Factoring

Identifying special situations in factoring

  • Difference of two squares
    • a2- b2 = (a + b)(a - b)
      • (x + 9)(x − 9)
      • (6x − 1)(6x + 1)
      • (x3 − 8)(x3 + 8)
  • Trinomial perfect squares
    • a2 + 2ab + b2= (a + b)(a + b) or (a + b)2
      • 16x2 - 8xy + y2 = (4x - y)2

      • 8xy + y2 + 16x2 = 16x2 + 8xy + y2 = (4x + y)2
      • a2 - 2ab + b2 = (a - b)(a - b) or (a - b)2
    • a2 - 2ab + b2 = (a - b)(a - b) or (a - b)2
  • Difference of two cubes
    • a3 - b3
      • 3 - cube root 'em
      • 2 - square 'em
      • 1 - multiply and change
        • x3-27 = (x-3)(x2+3x+9)
        • 8y3-125 = (2y-5)(2y2+10y+25)
        • s3-1 = (s-1)(s2+s+1)
  • Sum of two cubes
    • a3 + b3
      • 3 - cube root 'em
      • 2 - square 'em
      • 1 - multiply and change
        • q3+1 = (q+1)(q2+q+1)
        • a3+125 = (a+5)(a2-5a+25)
        • h3+64 = (h+4)(h2-4h+16)
  • Binomial expansion
    • (a + b)3 = (a+b)(a+b)(a+b)
    • (a + b)4 = (a+b)(a+b)(a+b)(a+b)

End Behaviors/ Naming Polynomials

Linear Equations:
y= mx+b
1 degree
0 turns

Domain - x values
Range - y values referred to as f(x)


When m is Positive:
domain → +∞, range → +∞ (rises on the right)
domain → -∞, range → -∞ (falls on the left)












When m is Negative
domain → -∞, range → +∞ (rises on the left)
domain → +∞, range → -∞ (falls on the right)












Quadratic Equations (parabolic equation)
y=ax²
2 degree
1 turn
(a+b)(c+d)
When a is Positive


domain → +∞, range → +∞ (rises on the right)
domain → -∞, range → -∞ (falls on the left)








When a is Negative


domain → +∞, range → -∞ (falls on the right)
domain → -∞, range → -∞ (falls on the left)








Naming Polynomials:
--Number of turns is always 1 less than the degree.

Degree:

0- Constant
1- Linear
2- Quadratic
3- Cubic
4- Quartic
5- Quintic
6 to ∞- nth Degree

Terms:

Monomial - one term
Binomial - two terms
Trinomial - three terms
Quadrinomial - four terms
Polynomial - two or more terms