11、设A＝B＝R(实数集)，如果A到B的映射射：x→x＋2，，x∈R，则则是从A到B的（） A. 满射而非单射 B. 单射而非满射 C. 一一映射

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河南成教 / 近世代数

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11、设A＝B＝R(实数集)，如果A到B的映射射：x→x＋2，，x∈R，则则是从A到B的（）

A. 满射而非单射

B. 单射而非满射

C. 一一映射

D. 既非单射也非满射

积分

近世代数

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