Stage 19 · Sets & Intervals — the Language of Functions

19.2.4 The Empty Set

19.2 Writing a Set Down: Two Notations

Point 4 of 5

Core idea

When no one meets the entry condition, the circle holds nothing at all, and this empty circle is written ∅.

Module goal. Master listing and rule-based notation, switching freely between "naming members one by one" and "stating one rule"

eastmath.com · 19.2 Writing a Set Down: Two Notations · 19.2.4 The Empty Set