IntroFoundations

Function Notation

Overview

f(x) is the universal language of calculus. Understanding how to read, evaluate, and interpret function notation is the essential first step.

Key Concepts

1

f(x) means: apply rule f to input x and get output f(x)

2

f(3) = evaluate the function at x = 3

3

Domain: all valid inputs x; Range: all possible outputs f(x)

4

y = f(x) — y and f(x) are interchangeable notations

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