Difference between revisions of "Contrapositive"
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Revision as of 13:36, 16 June 2015
Definition
Given the statement A⟹B (see implies) the contrapositive of this is: ¬B⟹¬A
Proof:
| A | B | A⟹B | ¬A | ¬B | ¬B⟹¬A |
|---|---|---|---|---|---|
| T | T | T | T | ||
| T | T | T | T | ||
| T | T | ||||
| T | T | T | T |
So as can be seen:
- [A⟹B]⟺[¬B⟹¬A]
For example see Injection
TODO: Find reference
