R (Real) I (Irrational) N (Natural) Q (Rational) W (Whole) Z (Integers) 04d Real Numbers, Sets, and Interval Notation Sets Set = a collection of objects the objects are elements of the set If B is a set, the notation a ∈ B means that a is an element in the set B and the notation c ∉ B means that c is not an element in the set B. Some sets can be listed with braces : for instance A = {1,2,3,4} (the set A has 4 elements which are 1,2,3,4) Some sets can be written using set builder notation: D = { x | x > 10} which is read D is the set of all x's such that x is greater than 10 Set Union, Intersection, or Empty: Union: Given H and G then H ∪ G means the set that contains the elements of H and G Intersection: H ∩ G means the set that contains just the elements H & G have in common Empty: ∅ means there are no elements in the set EX: Given H = {1,2,3,4,5} G = {4,5,6,7,8} M = {9,10,11} H∩G= H∪ G= M∩G= H ∪ M= M ∪ G= H∩M= H∩ G∩M = H∪G∩M = Ex 5:__________________ 25:_________________ 1/7:_________________ 3π:_________________ Objective: Identify and classify real numbers, sets of numbers, and represent numbers using interval notation