102 - naming sets and types of sets

7/31/2019 102 - Naming Sets and Types of Sets

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S E T SNaming Sets

Types of Sets


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The set of months in a year.

Well defined or not?

The set of large numbers.The set of most interesting

students in this classThe set of continents in the

world


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Give two elements of set A.

A={4, 8, 12, 16}

What is n(D)?

Give one subset of D.

How many subsets does set D

have?


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HOMEWORK:

CHECK YOUR OWN PAPER.1. Well defined2. Not well defined3. Well defined

4. Well defined5. Not well definedQUESTIONS?


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3 WAYS TO INDICATE

A SET

1. Roster Method (Listing)2. Rule Method3. Set Builder Notation


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The set of monthsin a year

By roster method:A={January, February,MarchDecember

List all the elements of the set.Use ellipsis if there are too many

elements.


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The set of months

in a year

By Rule MethodA is the set of months in ayear

Describe the common property ofthe elements in a set without

enumerating the elements.


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The set of months

in a yearBy Set Builder Notation

A={x | x is a month in a year}

Treat each element as x. State the

condition. x must satisfy the condition

A is the set of all elements of x such thatx is a month in a year.


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CONTINENTS IN THE

WORLD

B = {Africa, Antartica, Asia,Australia, Europe, North America,

South America}

B is the set of continents in theworld

B = {x | x is a continent}


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DEFINTION

UNIT SET A set with only one element. Its

cardinality is always 1

C = {1}D = {green}

E = {Madagascar}

How many subsets does a unit set

have?


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DEFINTION

EMPTY SET OR NULL SET A set that has no elements.Its cardinality is always 0.

It is symbolized by or { }.

F = { }

How many subsets does a null set

have?

Why cant we use { } to denote a

null set?


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DEFINTION

FINITE SET A set whose elements can be

counted.

G = {2, 4, 5, 6}H = {a,b,c}

I = {11, 12, 20}

What is the n (E) ?


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DEFINTION

INFINITE SET A set whose elements cannot

be counted. It has an unlimitednumber of elements

J = {2, 4, 5, 6,} K = {a,b,c ,}

L = {11, 12, 13,}


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What is a unit set?What is a null set?

How is infinite set differentfrom a finite set?


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DEFINTION

JOINT SETS Sets with common elements

L = {2, 4, 6}M = {4,5,6,7}

What are the common elements of Land M?


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DEFINTION

DISJOINT SETS Sets without common elements.

N = {12, 14, 16}O = {11,13,15,17}


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DEFINTION

EQUAL SETS Sets with exactly the sameelements regardless of the

order.

P = {a, b, c, d}Q = {b, c, d, a}R = {d, a, c, b}


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DEFINTION

EQUIVALENT SETS Sets with exactly the same

cardinality.

S = {1, 2, 3, 4}T = {a, b, c, d}

How are equivalent setsdifferent from equal sets?


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What are a joint sets?What are a disjoint sets?

What are equal sets?What are equivalent sets?


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PracticeExercisesB and C.


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HOMEWORK:

CHECK YOUR OWN PAPER.A. B.

1. 8 1. X = {6,7,8,9,10,11}2. 1 2. M = {x | x is a multiple

3. 2of 10

}4. 16 3. Tis the set of three5. 64 basic needs of a person


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SYNTHESIS

[Journal]:Write 3 important points that

you learned about todaystopic.

102 - naming sets and types of sets

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