I've been bogging down for a while but got nowhere.
Use rules of inference to show that
Thanks in advance
It does not seem to follow. Consider the assignment where p, q, r, s are true and t, u are false. Then it seems to me that all premises are true but u is false.
Also, could you write an example of inference? There are dozens of way to write proofs, from completely formal to English text. I don't know what style you use.
Check out the link please
List of rules of inference - Wikipedia, the free encyclopedia