I'm a little lost with this, can you guys provide full solutions?
The following propositions are tautologies, prove each one of them without truth table.
This is (Where is a tautology.) Is this right? When can I apply ? Only when having all or ?
2) I dunno how to solve this one.
3) I dunno how to solve this one either.
This would be How do I proceed there?
5) Help here too.
6) Another help here.
We have What's next?
8) Help here again
9) Need help here too.
That's it, I'm lost with this, I hope you can help me.