Vocab Vault
What is the term for a collection of distinct objects?
A Ser
8 belongs to…
N,W,Z,Q,R
{1,2,3,4}
{x∣ x∈N , x≤4}
Equal, Equivalent, or Neither
{1,2,3} and {3,2,1}
Equal
Definition of a subset
A set that contains some but not all elements of another set;
What is the symbol that means “is an element of”?
∈
0 belongs to…
W,Z,Q,R
Odd natural numbers less than 12 (in set builder)
{x∣ x∈N, x is odd , x<12}
Finite or Infinite
{1,2,3,4,5}
Finite
Number of Proper subsets of {a,b}
→ Answer: 2^2 −1= 4 - 1 = 3 proper subsets
What is the difference between a finite set and an infinite set?
A finite set has a countable number of elements; an infinite set has no end.
-4 belongs to…
Z,Q,R
{x | x ∈ ℕ, x ≤ 5}
{1, 2, 3, 4, 5}
Equal, Equivalent, or Neither
{a, b, c, d, e} and {lions, tigers, bears, donkeys, fish}
Equivalent
n(A) for {2,4,6,8,10}
5
What is the name for a set with no elements?
The empty set or ∅
π (pi) belongs to…
R\Q (irrational) , R
{x | x ∈ ℤ, -4 ≤ x ≤ 4}
{-4, -3, -2, -1, 0, 1, 2, 3, 4}
Finite or Infinite
Set of all even integers
Infinite
A = {-100, -50, 0, 50, 100}
B = {-100 , 100}
___ ⊂ ___
B ⊂ A
Give an example of two sets that are equivalent but not equal.
{1,2,3} and {a,b,c} — same number of elements, different elements.
Find a number in Q but not in Z.
1/2, 3/4, 0.3 — it’s a rational number but not an integer
{0,5,10,15,20}
{x∣ x∈W , x is a multiple of 5, x≤20}
Finite or Infinite
{x| x ∈ ℤ , -1,000,000 < x < 1,000,000}
Finite
A = {x| x ∈ W , x ≤ 7}
255