Stage 19 · Sets & Intervals — the Language of Functions

19.3.1 Subset

19.3 Between One Set and Another

Point 1 of 5

19.3.1 Subset

Core idea

The small circle sits entirely inside the big one — every member of A is also a member of B, written A⊆B.

Module goal. Use the "circle inside a circle" picture to understand subsets, proper subsets, and equality, building comparisons between sets
eastmath.com · 19.3 Between One Set and Another · 19.3.1 Subset