Chapter 3.1 – 3.3 Relations & Functions Alg. 2 Notes Name:__________________ Date:________________ Assignment:

Domain and Range Domain = the set of all x-values. Range = the set of all y-values. List the domain and range of the relation {(a,1), (b,2), (c,3), (e,2)} D: R:

Set Builder Notation:{x I x  3} Example: Use the set {1,2,3,…,10} Find {x I x ≥ 7} Example: write the following using set builder notation { 4,5,6}

Set Builder Notation: Example: Use the set {0,2,4,6,8} Find {x I 2 < x ≤ 8} Example: write the following using set builder notation { 0,1,2,3,4,….}

Cartesian Coordinate System

Checking Solutions: Plug in! Determine if (-1,4), (0,6) are solutions to y = -2x + 5

Graphing Equations: 𝑦= 𝑥 2 𝑦= 𝑥 2 - 2 Meet the parabola guy! Get to know him now. He will be your friend by the end of the year  𝑦= 𝑥 2 𝑦= 𝑥 2 - 2

Which ones are Functions? b)(5, 8), (-2, 3), (3, 10), (-2, -6) d) c)

Sometimes we define domain by what it can’t be! Function Notation: Example : Evaluate f(-2) for f(x) = -2x2 – 1 Finding Domain (1st degree) State what values are acceptable When are values not acceptable? If they make the denominator = 0 or a Square root negative like… f 𝑥 = 𝑥−3 Sometimes we define domain by what it can’t be! Domain = {x | x } Domain = {x | x }

Practice: 1) Given f(x) = 2x + 6 a)What is the domain? b)Find f(3) Find h(-6)

Give the Domain and Range: