1. Ch1.3_UnionAndIntersectionOfSets.notebook August 23, 2011
Warm Up
What set of numbers includes all of the following
elements
{­2, 0, π, 3.5, 7}
Give an example of a rational number
Aug 22­8:38 AM
Ch. 1.3
Union and Intersection of Sets
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2. Ch1.3_UnionAndIntersectionOfSets.notebook August 23, 2011
Venn Diagram
U
Set B
Set A
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Union
The union contains ALL the elements that are in Set A, Set B, or both.
A ∪ B
U
Set B
Set A
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3. Ch1.3_UnionAndIntersectionOfSets.notebook August 23, 2011
Intersection
The intersection contains only the elements that are in Set A and Set B
A ∩ B
U
Set B
Set A
Aug 22­8:45 AM
Complement
The complement of a set contains all the elements that
are NOT in the Set
A'
U
Set B
Set A
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4. Ch1.3_UnionAndIntersectionOfSets.notebook August 23, 2011
Disjoint
No shared elements
(no overlap)
U
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A = {1,3,5}
Example B = {3,6}
U = {1,2,3,4,5,6,7}
C = {2,4}
A B C
U
Find the following C'
A ∩ B
A∪B
A∩C
C∪B
Aug 22­8:56 AM
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5. Ch1.3_UnionAndIntersectionOfSets.notebook August 23, 2011
Compound Inequality
Combination of 2 inequalities
A = whole numbers greater than 2
B = integers less than 7
A = {3,4,5,6...}
B = {...,­2,­1,0,1,2,3,4,5,6}
A ∪ B =
A∩B=
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Example
A = {x | x is a positive real number}
B = {x | x is a real number less than or equal to 9}
A
­5 ­4 ­3 ­2 ­1 0 1 2 3 4 5
B
­5 ­4 ­3 ­2 ­1 0 1 2 3 4 5
A∩B
­5 ­4 ­3 ­2 ­1 0 1 2 3 4 5
A∪B
­5 ­4 ­3 ­2 ­1 0 1 2 3 4 5
Aug 22­12:16 PM
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6. Ch1.3_UnionAndIntersectionOfSets.notebook August 23, 2011
Using the set of real numbers
as the replacement set, graph the solution
to the following compound inequalities
x < 5 AND x ≥ -3
­5 ­4 ­3 ­2 ­1 0 1 2 3 4 5
x ≥ 4 OR x < 0
­5 ­4 ­3 ­2 ­1 0 1 2 3 4 5
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Page 19
#27 U = {1,2,3,4,5,6,7,8,9}
A = {x | x is a whole number and x > 2 and x < 8}
B = {1,3,5,7,9}
C = {0,1,2,3,4,5}
D = {0,3,6,9}
Find the solution set
B ∪ ( C ∩ D )
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7. Ch1.3_UnionAndIntersectionOfSets.notebook August 23, 2011
Check answers with other people in your row
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