Prove this proposition is a tautology: [(p ∨ q) ∧ (p → r) ∧ (q → r)] → . . . You'll need to complete a few actions and gain 15 reputation points before being able to upvote Upvoting indicates when questions and answers are useful What's reputation and how do I get it? Instead, you can save this post to reference later
How to prove ⊢B→(A→B) (no premise) using natural deduction? One of the problems in my latest logic homework asks us to prove ⊢B→(A→B) using any of the many rules of natural deduction I've been at it for several minutes yet can't seem to find a way to solve
What does $\\rightarrow$ mean in $p \\rightarrow q$ The → → symbol is a connective It's a symbol which connects two propositions in the context of propositional logic (and its extensions, first-order logic, and so on) The truth table of → → is defined to be that p → q p → q is false if and only if p p is true and q q is false Indeed this is the same meaning of , but the difference is that p q p q is a statement about propositions