0 votes
4
Which of the following well-formed formulas are equivalent?$P \rightarrow Q$$\neg Q \rightarrow \neg P$$\neg P \vee Q$$\neg Q \rightarrow P$
0 votes
6
1 votes
13
p ->(q->r). Could you please tell me how it is a tautology?
0 votes
14
1 votes
15