RELATIONS & FUNCTIONS CHAPTER 4

Relations A relation is any set of ordered pairs. The set of input values (or x-coordinate) is called the domain. The set of output values (or y-coordinates) is called the range.

Domain is the set of all x values. Domain & Range Domain is the set of all x values. Range is the set of all y values. {(1, 1), (1, 2), (1, 3), (2, 1), (2, 2), (2, 3)} Example 1: Domain- Range- D: {1, 2} R: {1, 2, 3} *you do not have to repeat numbers in your domain and range answer if they are repeated in the coordinates, but they must be in numerical order

Example 2: -8 -6 -4 -2 2 4 6 8 8 6 4 2 -2 -4 -6 -8 -4 -8 -3 6 -4 2 6 -8 -6 -4 -2 2 4 6 8 8 6 4 2 -2 -4 -6 -8 x y -4 -8 -3 6 -4 2 6 Domain: {-4, -3, 0, 2} Range: {-8, -4, 6}

Graphs A Relation can be represented by a set of ordered pairs of the form (x,y) Every equation has solution points (points which satisfy the equation).

Ex. Graph y = 2x + 2 x y -2 -1 1 2 Plug the x values into the equation to solve for y (x values will be given to you)

Ex . Graph y = x² - 5 x y -2 -1 1 2

Ex . Determine whether the given ordered pairs are solutions of this equation. (-1, -4) and (7, 5); y = 3x -1