IB SL AA Notation

ℕ

The set of positive integers and zero, {0, 1, 2, 3, …}

ℤ

The set of integers, {0, ±1, ±2, ±3, …}

ℤ⁺

The set of positive integers, {1, 2, 3, …}

ℚ

The set of rational numbers

ℚ⁺

The set of positive rational numbers, {x | x ∈ ℚ, x > 0}

ℝ

The set of real numbers

ℝ⁺

The set of positive real numbers, {x | x ∈ ℝ, x > 0}

{x₁, x₂, …}

The set with elements x₁, x₂, …

{x | …}

The set of all x such that

∈

Is an element of

∉

Is not an element of

∅

The empty (null) set

U

The universal set

a½, √a

Square root of a (if a ≥ 0 then √a ≥ 0)

a^(1/n), ⁿ√a

nth root of a

a⁻ⁿ

Reciprocal of aⁿ (1/aⁿ)

≡

Identity

⇒

Implies

⇔

Implies and is implied by (if and only if)

Δ

The discriminant of a quadratic equation (b² - 4ac)

f⁻¹

The inverse function of the function f

f ∘ g

The composite function of f and g

∫ [a,b] y dx

The definite integral of y between x = a and x = b

uₙ

The nth term of a sequence or series

d

The common difference of an arithmetic sequence

r

The common ratio of a geometric sequence

Sₙ

The sum of the first n terms of a sequence

S∞

The sum to infinity of a sequence

Σ uᵢ

The sum of u₁ + u₂ + … + uₙ

n!

n factorial (n × (n-1) × … × 1)

ⁿCᵣ

The number of ways to choose r items from n

[AB]

The line segment with end points A and B

AB

The length of the line segment [AB]

(AB)

The line containing points A and B

Â

The angle at A

CÂB

The angle between [CA] and [AB]

Δ ABC

The triangle with vertices A, B, and C

σ²

Population variance

σ

Population standard deviation

x̄

The sample mean of a set of observations

B(n, p)

Binomial distribution with parameters n and p

N(μ, σ²)

Normal distribution with mean μ and variance σ²

r

Pearson's product-moment correlation coefficient