Alg. 2 Unit 1- All About Functions

this is a section of Unit 1 Algebra 2!!

Curly Braces { }

defines a set

What does {1, 2, 3} mean?

the set containing 1, 2, 3

Vertical Bar | (or Colon : )

such that

What does {x ∈ ℝ| x > 0) mean?

the set of all real numbers x such that x > 0. (so basically it’s all positive real numbers!)

Element of ∈

is in

What does 3 ∈ {1, 2, 3} mean?

3 is an element of the set {1, 2, 3}

Not an element of ∉

is not in

What does 4 ∉ {1, 2, 3} mean?

4 is not an element of the set {1, 2, 3}.

Integers ℤ

all whole numbers

What does x ∈ ℤ mean?

x is an integer.

Natural Numbers ℕ

positive whole numbers excluding zero

What does n ∈ ℕ mean?

n is a natural number.

Real Numbers ℝ

all numbers on the number line

What does x ∈ ℝ mean?

x is a real number

What does {x ∈ ℤ | x < 5} mean?

the set of integers less than 5

What does {x ∈ ℕ | 1 < x ≥ 5 } mean?

natural numbers greater than 1 but less than or equal to 5

What does {x ∈ ℝ| x > 0 } mean?

all real numbers greater than 0

What does { x ∈ ℝ | x ≥ 100 } mean?

all real numbers greater than or equal to 100.