MATHEMATICS · CORE LANGUAGE

Functions

A function assigns each allowed input exactly one output. Functions are the language of change, dependence and mathematical models — connecting algebra, geometry, calculus, probability and beyond.

y = f(x)

THE FOUR QUESTIONS

Understand every function through the same lens.

01 · INPUT

What is the domain?

Which input values are allowed? Restrictions can come from denominators, roots, logarithms or the model itself.

02 · OUTPUT

What is the range?

Which output values can the function actually produce?

03 · SHAPE

What does the graph do?

Intercepts, symmetry, growth, turning points and asymptotic behaviour reveal structure visually.

04 · OPERATION

How can it be transformed?

Shift, scale, reflect and combine functions without losing track of what changes.

05 · CONNECTION

Can it be inverted?

Inverse functions reverse input and output when the original function is one-to-one on the chosen domain.

06 · COMBINATION

Can functions be composed?

Composition feeds the output of one function into another and builds more complex models.

FUNCTION LIBRARY

Learn the core building blocks.

WHY FUNCTIONS MATTER

Functions connect algebra to calculus.

Equations ask where expressions are equal. Functions describe entire relationships. Calculus then studies how those relationships change — through limits, derivatives and integrals.

EquationsFunctionsLimitsDerivativesIntegrals