I'm trying to do a bunch of proofs to get better at them but it seems like I need some help with negation. Can anyone who has time prove the following arguments? I would really appreciate it!
¬(P ∧ ¬Q), ¬P → Q ∴ Q
P → ¬Q, ¬Q → P ∴ ¬(Q ↔︎ P)
Q → P, ¬P ∨ S ∴ ¬S → ¬Q
R ∨ (P ∨ Q), Q → ¬Q, R → P ∴ P
Thank you!