This document discusses the concepts of union and intersection of sets by defining them, providing examples of how to find the union and intersection of sets using Venn diagrams, and giving practice problems for students to find the union and intersection of various sets. It aims to help students understand and be able to apply the concepts of union and intersection of sets by the end of the lesson.

1. Union and Intersection
of Sets
Prepared by: Ms. Marinel C. Bayron

2. • Describe and define union and intersection of sets.
• Find the union or intersection of sets.
• Use Venn diagrams to represent the union and intersection of sets.
By the end of this lesson, you will...

3. FAVORITE SUBJECTS

4. Answer the follow-up questions:
1. If we will combine all their favorite
subjects, what are they?
2. Is there a subject that they both like?
What is this?
3. Do you have your favorite subjects too?

5. Given the pictures below, answer the following
questions:

6. 1. Which of the following shows the combination of set A
and set B? How many elements are there?

7. 2. What element/s contain/s in both A and B How many
element/s is/are there?

9. a. How will you describe the given
diagram?
b. How many sets are there? What are
their elements?
c. Is there a common element/animal in
both sets?

10. Union and
Intersection of sets
may be represented
using Venn Diagrams.

11. Universal set of Animals:
E = Everything = { Fish, Eels, Platypus, Penguins, Eagles, Bats }

12. Intersection of Sets
“Water Animals” and “Two Legged Animals” .
When we do this, we find that Penguins belong in both groups:
E = Everything = { Fish, Eels, Platypus, Penguins, Eagles, Bats }
Water Animals={Fish, Eels, Platypus, Penguin}
Two Legged Animals = {Eagles, Bats, Penguins }

14. Union of Sets
The union of two sets is everything that
is contained within the two circles
joined together.

16. The cardinality of a set is the number of
elements contained in that set.
a. Who are the personalities given in Activity 1 in Set A? in Set B?
b. Who is common in both sets? Why?
c. How will you differentiate union and intersection of sets?
d. Can you give your own real-life examples of these sets?

17. Try this
Given: A = {a,e,i,o,u}
B = {a,b,c,d,e}
Find:
1. A ∩ B
2. A U B

18. Assignment ½ crosswise:
1. A U B
2. A ∩ B
3. A U C
4. A ∩ C