surjective function

满射

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

Other names / variants: surjection

Translation evidence: Literature usage

Meaning in context

A function f:A→B whose image is all of B.

像等于整个陪域 B 的映射 f:A→B。

Example

n↦n+2n\mapsto n+2 is surjective on Z\mathbb Z.

Usage and distinctions

Surjectivity can change when the codomain changes even if the formula and domain stay fixed.

Recommended reading in this subject · Preparation & skip guidance

Definition sources

  1. Avigad, Hua, Lewis and van Doorn — Logic and Proof§15.1 The Function Concept; §15.2 Injective, Surjective, and Bijective Functions; §15.3 Functions and Subsets of the Domain · Checked 2026-10-14

Translation sources

  1. 高等教育出版社 — 数学证明 通往高等数学的阶梯（第4版）影印版，官方中文目录官方中文目录：§10.2 单射函数与满射函数（名称证据，非正文定义证据） · Checked 2026-10-14
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