Setamp;IntervalNotation设置amp；间隔符号

,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,*,Click to edit Master title style,Click to edit Master text styles,Second level,Third level,Fourth level,Fifth level,*,*,Set&Interval Notation,Sets and Elements,A,set,is a collection of objects.To denote a set we often enclose a list of its,elements,with braces.This is called the,Roster Method,.,Natural Numbers 1,2,3,4,5,Whole Numbers 0,1,2,3,4,Integers,-3,-2,-1,0,1,2,3,Since every natural number is also a whole number,we say that the set of natural numbers is a,subset,of the set of whole numbers.,Set Builder Notation,A set can also be written in,set builder notation,.In this method,we write a rule that describes what elements are in a set.For example:,x|x is greater than 2.,The graph would look like either of the following:,OR,The set of all x,Such that,A rule that describes membership in the set,0,0,Example 1:Writing&Graphing Set Notation,x,0,x,2,-2 x 1,Interval Notation,Graphs of sets of real numbers are often portions of a number line called,intervals,.The interval can be written in,interval notation,.,For example,for-2 x 1 we write the interval notation as(-2,1.Parentheses are used to show it does not contain that number,where brackets show it does contain that value.,Example 2:Graph&Write in Interval Notation,x|x is less than 9.,x|x is greater than or equal to 6.,x|x is greater than or equal to-5 and less than or equal to 6.,x|x is great than 2 and less than or equal to 8.,OR Compound Inequalities and Union,The graph of the set x|x is less than-2 or greater than 3 is shown below.This graph is called the,union,of two intervals and can be written in interval notation as seen below.,(-,-2)U(3,),0,Example 3:Unions,x|x is greater than 5 or less than 4.,x|x is less than or equal or-1 or greater than 2.,