Proof
| Proposition | Derivation |
|---|---|
| Given | |
| Given | |
| Material implication | |
| Modus ponens |
| Proposition | Derivation |
|---|---|
| Given | |
| Given | |
| Material implication | |
| Transposition | |
| Modus ponens |
Read more about this topic: Disjunctive Syllogism
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