7: Injection

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A definition of injection

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Topics

About: set

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The table of contents of this article

• Starting Context
• Target Context
• Orientation
• Main Body
• 1: Definition

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Starting Context

• The reader knows a definition of set.
• The reader knows a definition of map.

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Target Context

• The reader will have a definition of injection.

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Orientation

There is a list of definitions discussed so far in this site.

There is a list of propositions discussed so far in this site.

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Main Body

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1: Definition

For any sets, $S_1$ and $S_2$, any map, $f:S_1\to S_2$, such that for any pair of distinct elements, $s_{11},s_{12}\in S_1$ such that $s_{11}\ne s_{12}$, $f(s_{11})\ne f(s_{12})$

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References

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