Definition 11.11 High School Mathematics · 第 11 章 — Functions and Variations Let fff be defined on a domain DDD symmetric about 000 (i.e. −x∈D-x \in D−x∈D whenever x∈Dx \in Dx∈D). The function fff is even if f(−x)=f(x)f(-x) = f(x)f(−x)=f(x) for all x∈Dx \in Dx∈D, and odd if f(−x)=−f(x)f(-x) = -f(x)f(−x)=−f(x) for all x∈Dx \in Dx∈D. 在原文中阅读 →