How to use the formal system with the basic rules of inference to derive the following?
~(P → Q)├ P
Derivations in sentential logic?
2014-02-27 2:31 am
回答 (1)
2014-02-27 6:07 pm
In case any of my rules don't match yours, I'm using this online reference:
http://www.mathpath.org/proof/proof.inference.htm
1. ~(P → Q) [premise]
2. ~(~P v Q) [1, material implication]
3. ~~P . ~Q [2, de Morgan's theorem]
4. P . ~ Q [3, double negation]
5. P [4, simplification]
http://www.mathpath.org/proof/proof.inference.htm
1. ~(P → Q) [premise]
2. ~(~P v Q) [1, material implication]
3. ~~P . ~Q [2, de Morgan's theorem]
4. P . ~ Q [3, double negation]
5. P [4, simplification]
收錄日期: 2021-04-24 09:29:17
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20140226183141AA407ZQ