Can you determine whether they are tautologies using other means? How do you prove that something is not a tautology using simplifications?
Which of the following propositional forms are tautologies.
(p implies (q implies r)) implies ((p and not q) or r)
(p and not q) or (q and not r) or (r and not p)
I need help in both questions, btw, simplify only, no truth table
Thanks!
Assume Definition of tautology: Statement that is always true.
Write first one as A->B and let p=q=r=F
Then A is F and B is F so A->B is False. Not a tautology.
Write second one as AorBorC and let p=q=r=F. Then A,B and C are false so AorBorC is false. Not a tautology.