subset

子集

Foundations & Logic · Undergraduate · Mathematics Resources editorial compilation (AI-assisted)

Translation evidence: Literature usage

Meaning in context

$A$ is a subset of $B$ if $x\in A$ implies $x\in B$ for every $x$.

若 A 的每个元素均属于 B，则 A 是 B 的子集。

Example

$\{2\}\subseteq\{2,5\}$.

Usage and distinctions

Use ⊆ inclusively; ⊊ requires inequality. The meaning of ⊂ varies between authors.

Recommended reading in this subject · Preparation & skip guidance

Definition sources

1. Avigad, Hua, Lewis and van Doorn — Logic and Proof§11.1 Elementary Set Theory; §11.4 Cartesian Product and Power Set · Checked 2026-10-14

Translation sources

1. 李文威 — 代数学方法，第一卷（作者源码）第1章「ZFC 公理一览」 · Checked 2026-10-14

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