Recall that -A \/ B is equivalent to A -> B and try rewriting the formulas you are given using this equivalence as much as possible.
I have 3 tasks to solve, and I believe that I've achieved correct answer, but I might be totally wrong.
The question is if these expressions are correct or incorrect (true/false)
a) C -> (A -> B) |= -C ^ (-A v B)
b) C -> A( -> B) |= -C v -A v B
c) -C v (-A v B) |= C->(A->B)
I'd appreciate your help, and solutions for these tasks.