CP 1 Sets and Functions 1

Question 1

what is a set

Answer 1

unordered collection of unique objects (called the elements of a set)

Question 2

What is the notation for a set

Answer 2

Capital letters for sets
lowercase for the elements

Question 3

example of notation for sets

Answer 3

if x is and element of X we write x∈X

Question 4

what is set roster notation

Answer 4

elements are explicitly listed (if there’s too many we use “…”)

Question 5

whats set builder notation

Answer 5

{elements|condititions for element}

ex
{x | x is positive}

Question 6

What does a bolded N mean

Answer 6

Set of natural numbers
(0,1,2,3,4,5)

Question 7

What would it mean if a bolded N had a + beside it

Answer 7

would mean the set of +e natural numbers
(1,2,3,4,5,6)

Question 8

What does a bolded Z mean

Answer 8

The set of all whole numbers
(-3,-2,-1,0,1,2,3)

Question 9

what does a bolded Q mean

Answer 9

set of all irrational #s (ratios / fractions)
(p/q| p,q ∈ Z and q=0)

Question 10

what is {}

Answer 10

empty set

Question 11

What is a subset + whats the sign

Answer 11

we say X is a subset of Y if every element of X is also an element of Y
denoted: X⊆Y
- we can also say Y is a superset of X

Question 12

what is a proper subset
denoted: ?

Answer 12

if X is a subset but not equal to Y (X⊆Y, X≠ Y)
denoted: X⊂Y

Question 13

if A= {2,3,5} then (2,3} and {3} are

Answer 13

Proper subsets